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Multimodal clinical parameters-based immune status associated with the prognosis in patients with hepatocellular carcinoma
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作者 Yu-Zhou Zhang Yuan-Ze Tang +4 位作者 Yun-Xuan He Shu-Tong Pan Hao-Cheng Dai Yu Liu Hai-Feng Zhou 《World Journal of Gastrointestinal Oncology》 2026年第1期75-91,共17页
Hepatocellular carcinoma presents with three distinct immune phenotypes,including immune-desert,immune-excluded,and immune-inflamed,indicating various treatment responses and prognostic outcomes.The clinical applicati... Hepatocellular carcinoma presents with three distinct immune phenotypes,including immune-desert,immune-excluded,and immune-inflamed,indicating various treatment responses and prognostic outcomes.The clinical application of multi-omics parameters is still restricted by the expensive and less accessible assays,although they accurately reflect immune status.A comprehensive evaluation framework based on“easy-to-obtain”multi-model clinical parameters is urgently required,incorporating clinical features to establish baseline patient profiles and disease staging;routine blood tests assessing systemic metabolic and functional status;immune cell subsets quantifying subcluster dynamics;imaging features delineating tumor morphology,spatial configuration,and perilesional anatomical relationships;immunohistochemical markers positioning qualitative and quantitative detection of tumor antigens from the cellular and molecular level.This integrated phenomic approach aims to improve prognostic stratification and clinical decision-making in hepatocellular carcinoma management conveniently and practically. 展开更多
关键词 Hepatocellular carcinoma Immune status PHENOTYPE Multimodal parameters PROGNOSIS
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Typhoon Kompasu(2118)simulation with planetary boundary layer and cloud physics parameterization improvements
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作者 Xiaowei Tan Zhiqiu Gao Yubin Li 《Atmospheric and Oceanic Science Letters》 2026年第1期41-46,共6页
This study introduces a new ocean surface friction velocity scheme and a modified Thompson cloud microphysics parameterization scheme into the CMA-TYM model.The impact of these two parameterization schemes on the pred... This study introduces a new ocean surface friction velocity scheme and a modified Thompson cloud microphysics parameterization scheme into the CMA-TYM model.The impact of these two parameterization schemes on the prediction of the movement track and intensity of Typhoon Kompasu in 2021 is examined.Additionally,the possible reasons for their effects on tropical cyclone(TC)intensity prediction are analyzed.Statistical results show that both parameterization schemes improve the predictions of Typhoon Kompasu’s track and intensity.The influence on track prediction becomes evident after 60 h of model integration,while the significant positive impact on intensity prediction is observed after 66 h.Further analysis reveals that these two schemes affect the timing and magnitude of extreme TC intensity values by influencing the evolution of the TC’s warm-core structure. 展开更多
关键词 Tropical cyclone Numerical simulation Planetary boundary layer parameterization SCHEME Cloud physics scheme
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Effect of total knee arthroplasty on the spinopelvic parameters: A systemic review and metanalysis
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作者 Mantu Jain Deb Kumar Pal +3 位作者 Rabi Narayan Sahu Bikash Ranjan Meher Binod Kumar Patro Sujit Kumar Tripathy 《World Journal of Orthopedics》 2025年第7期126-133,共8页
BACKGROUND Sagittal spinopelvic alignment(SSA)is essential for preserving a stable and effective upright posture and locomotion.Although alterations in the SSA are recognised to induce compensatory modifications in th... BACKGROUND Sagittal spinopelvic alignment(SSA)is essential for preserving a stable and effective upright posture and locomotion.Although alterations in the SSA are recognised to induce compensatory modifications in the pelvis,hips,and knees,the inverse relationship concerning knee pathology undergoing total knee arthroplasty(TKA)has been examined by a limited number of studies,yielding inconclusive results.AIM To generate evidence of the effect of TKA on the SSA from existing literature.METHODS Databases like PubMed,EMBASE,and Scopus were used to identify articles related to the“knee spine syndrome”phenomenon using a combination of subject terms and keywords such as“spinopelvic parameters”,“sagittal spinal balance”,and“total knee arthroplasty”were used with appropriate Boolean operators.Studies measuring the SSA following TKA were included,and research was conducted as per preferred reporting items for systematic review and metaanalysis guidelines.RESULTS A total of 475 participants had undergone TKA,and six studies measuring SSA were analysed.Following TKA,pelvic tilt was the only parameter that showed significant changes,while lumbar lordosis(LL),pelvic incidence,and sacral slope were non-significant,as evident from the forest plots.CONCLUSION The body's sagittal alignment is a complex balance between pelvic,spine,and lower extremity parameters.TKA,while having the potential to correct the flexion contracture,can also correct it.Still,the primary SSA for spinal pathology,i.e.,LL,may not be corrected in patients with co-existent spinal degenerative disease. 展开更多
关键词 Spinopelvic parameters Total knee arthroplasty Pelvic parameters Lower extremities parameters META-ANALYSIS
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Optimizing the key parameter to accelerate the recovery of AMOC under a rapid increase of greenhouse gas forcing
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作者 Haolan Ren Fei Zheng +1 位作者 Tingwei Cao Qiang Wang 《Atmospheric and Oceanic Science Letters》 2025年第1期39-45,共7页
Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in c... Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in climate models.Previous studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC simulations.In this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after its collapse.Through a new optimization strategy,the extra freshwater flux(FWF)parameter is determined to be the dominant one affecting the AMOC’s variability.The traditional ensemble optimal interpolation(EnOI)data assimilation and new machine learning methods are adopted to optimize the FWF parameter in an abrupt 4×CO_(2) forcing experiment to improve the adaptability of model parameters and accelerate the recovery of AMOC.The results show that,under an abrupt 4×CO_(2) forcing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter slowly.However,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,according to their physical relationship with FWF on the interdecadal timescale. 展开更多
关键词 Recovery of AMOC 4×CO_(2) forcing Key parameter parameter estimation Data assimilation Machine learning
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Antenna Parameter Calibration for Mobile Communication Base Station via Laser Tracker
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作者 LI Junqiang CHEN Shijun +2 位作者 FENG Yujie FAN Jiancun CHEN Qiang 《ZTE Communications》 2025年第3期89-95,共7页
In the field of antenna engineering parameter calibration for indoor communication base stations,traditional methods suffer from issues such as low efficiency,poor accuracy,and limited applicability to indoor scenario... In the field of antenna engineering parameter calibration for indoor communication base stations,traditional methods suffer from issues such as low efficiency,poor accuracy,and limited applicability to indoor scenarios.To address these problems,a high-precision and high-efficiency indoor base station parameter calibration method based on laser measurement is proposed.We use a high-precision laser tracker to measure and determine the coordinate system transformation relationship,and further obtain the coordinates and attitude of the base station.In addition,we propose a simple calibration method based on point cloud fitting for specific scenes.Simulation results show that using common commercial laser trackers,we can achieve a coordinate correction accuracy of 1 cm and an angle correction accuracy of 0.25°,which is sufficient to meet the needs of wireless positioning. 展开更多
关键词 antenna parameter parameter measurement coordinate transformation point cloud laser track angle correction
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A Hybrid Simulation-Experimental Method for Deriving Equivalent Dynamic Parameters of O-Ring Support Systems
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作者 LIU Yi YE He +3 位作者 ZHANG Lingfeng LI Shujia CHEN Ge WANG Yongxing 《Journal of Donghua University(English Edition)》 2025年第4期425-434,共10页
The high-speed winding spindle employs a flexible support system incorporating rubber O-rings.By precisely configuring the structural parameters and the number of the O-rings,the spindle can stably surpass its critica... The high-speed winding spindle employs a flexible support system incorporating rubber O-rings.By precisely configuring the structural parameters and the number of the O-rings,the spindle can stably surpass its critical speed points and maintain operational stability across the entire working speed range.However,the support stiffness and damping of rubber O-rings exhibit significant nonlinear frequency dependence.Conventional experimental methods for deriving equivalent stiffness and damping,based on the principle of the forced non-resonance method,require fabricating custom setups for each O-ring specification and conducting vibration tests at varying frequencies,resulting in low efficiency and high costs.This study proposes a hybrid simulation-experimental method for dynamic parameter identification.Firstly,the frequency-dependent dynamic parameters of a specific O-ring support system are experimentally obtained.Subsequently,a corresponding parametric finite element model is established to simulate and solve the equivalent elastic modulus and equivalent stiffness-damping coefficient of this O-ring support system.Ultimately,after iterative simulation,the simulated and experimental results achieve a 99.7%agreement.The parametric finite element model developed herein can directly simulate and inversely estimate frequency-dependent dynamic parameters for O-rings of different specifications but identical elastic modulus. 展开更多
关键词 O-RING equivalent dynamic parameter forced non-resonance method inverse parameter estimation dynamic simulation
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Analysis and estimation of wave-induced Doppler shift from low-incidence-angle RAR based on sea state parameters
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作者 Jing Ye Yong Wan +3 位作者 Chenqing Fan Yongshou Dai Yisen Yang Xiangying Miao 《Acta Oceanologica Sinica》 2025年第9期169-182,共14页
The research on ocean dynamics information plays a crucial role in understanding ocean phenomena, assessing marine environmental impacts, and guiding engineering designs. The Doppler information observed by radars ref... The research on ocean dynamics information plays a crucial role in understanding ocean phenomena, assessing marine environmental impacts, and guiding engineering designs. The Doppler information observed by radars reflects sea surface dynamics, to which ocean waves make important contributions. Low-incidence-angle real aperture radar(RAR)demonstrates great potential for independently observing vectorial Doppler information on the ocean surface. To systematically characterize and accurately estimate the wave-induced Doppler frequency shift(WVF) from lowincidence-angle RAR, this study conducts comprehensive influencing factor analysis and establishes sea-stateparameterized WVF models. First, a simulated WVF dataset is generated under a rotating low-incidence-angle RAR.The feature parameters of WVF are then determined by analysing contributing factors including wind waves, swells,and sea state parameters. Furthermore, two WVF models(WVF_Ku P9 with 9 inputs and WVF_Ku P4 with 4 inputs) are constructed by the Transformer encoder for different application scenarios. Both models achieve high accuracy for WVF estimation with root mean square errors(RMSE) of 1.874 Hz and 2.716 Hz, respectively. The reliability and superiority of the proposed models are validated through comparisons with the Ka DOP, which is a typical geophysical model function(GMF). The findings in this paper advance the understanding of WVF characteristics and generation mechanisms. The proposed estimation models can provide reliable estimates, offering critical references for lowincidence-angle RAR applications such as ocean surface current retrieval. 展开更多
关键词 wave-induced Doppler shift parameter estimation low-incidence-angle real aperture radar sea state parameters Transformer encoder
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Influence of Processed Mustard Seed Meals on Growth and Health Parameters in Indian Major Carps
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作者 Shivanshu Garg Himanshu Punetha +8 位作者 Anant Deogaonkar Deepshree Kumar Ashutosh Mishra AshokKumar Verma Nityanand Pandey Ranjeet Singh Saurabh Gangola Sunil Kumar Amit Mittal 《Research in Ecology》 2025年第2期93-105,共13页
The current investigation focuses on intertwined relationships of ecology and aquaculture for the benefit of farmers involved in fish farming practices.The study evaluated glucosinolate reduction in black,brown,and wh... The current investigation focuses on intertwined relationships of ecology and aquaculture for the benefit of farmers involved in fish farming practices.The study evaluated glucosinolate reduction in black,brown,and white mustard meals as fish feed ingredients for Indian Major Carps.Fish were fed with 10%mustard meal-supplemented diets in three forms:Raw(R),Anti-nutritional Rich(AR),and Anti-nutritional Lowered(AL),alongside a control group using floating feed.The three-month indoor experiment(September-November 2023)was conducted in FRP tanks with triplicate treatments.Blood analysis revealed compromised health in AR-fed carps,with reduced hemoglobin levels in rohu,catla and mrigal and elevated total leukocyte counts indicating inflammation in all the three carps studied here.Liver function was impaired in AR-fed fish,shown by increased alanine transaminase levels,highest in rohu followed by mrigal and catla.Histopathological examination of AR-fed carps liver tissue revealed necrotic spots,deformed hepatocytes,and significant vacuolation.In contrast,AL-fed fish demonstrated improved health parameters through Complete Blood Count analysis,liver function tests,and histo-pathological observations,suggesting successful reduction of anti-nutritional factors in the processed mustard meals.In near future,replacement of unprocessed seed meal with processed seed meal will lead to economic gains in fish farming. 展开更多
关键词 Biochemical parameters GLUCOSINOLATES Growth parameters Histo-Pathological Analysis Indian Major Carps Liver Function Test
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Preoperative malignancy risk assessment in pancreatic cystic neoplasms using clinical and laboratory parameters
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作者 Hüseyin Fahri Martli Fatih Acehan +4 位作者 AhmetŞimşek EdaŞahingöz Aziz Ahmet Sürel Sadettin Er Mesut Tez 《World Journal of Gastrointestinal Surgery》 2025年第11期176-183,共8页
BACKGROUND Pancreatic cystic neoplasms(PCNs)are increasingly detected due to advancements in radiographic techniques,with a prevalence of approximately 15%in the general population.These lesions range from benign to p... BACKGROUND Pancreatic cystic neoplasms(PCNs)are increasingly detected due to advancements in radiographic techniques,with a prevalence of approximately 15%in the general population.These lesions range from benign to premalignant and malignant,posing a diagnostic challenge.Accurate differentiation is critical,as premalignant and malignant PCNs often require surgical intervention,while benign cysts may only need monitoring unless symptomatic.Current diagnostic methods,including cross-sectional imaging,endoscopic ultrasonography,and endoscopic ultrasonography-guided fine-needle aspiration/biopsy,are specialized,not universally available,and have variable accuracy.Clinical and laboratory parameters such as carbohydrate antigen 19-9(CA 19-9),neutrophillymphocyte ratio,platelet-lymphocyte ratio,and red cell distribution width(RDW)have been associated with malignancy risk,though only CA 19-9 is guideline-supported.AIM To assess the malignancy risk of PCNs using preoperative clinical and routine laboratory parameters.METHODS A retrospective cohort study analyzed 70 patients who underwent surgery for PCNs at Ankara Bilkent City Hospital between February 2019 and March 2023.Patients were categorized into group A(benign or low-grade dysplasia,n=40)and group B(malignancy or high-grade dysplasia,n=30)based on postoperative pathology.Preoperative demographic and laboratory parameters,including age,RDW,albumin,and CA 19-9,were compared.Univariate and multivariate logistic regression analyses identified independent predictors of malignancy.Receiver operating characteristic curve analysis evaluated predictive performance,with internal validation using bootstrapping.RESULTS Group B patients were older(69.86±9.58 years vs 52.74±16.85 years,P<0.001)and had a higher incidence of diabetes mellitus(57.1%vs 21.4%,P=0.002).RDW(16.2%vs 13.7%,P<0.001),platelet-lymphocyte ratio(178 vs 126,P=0.008),and CA 19-9(21.7 U/mL vs 9.3 U/mL,P=0.009)were significantly higher in group B,while albumin was lower(41 g/L vs 45 g/L,P=0.008).Multivariate analysis identified age[odds ratio=1.067,95%confidence interval(CI):1.014-1.122,P=0.012]and RDW(odds ratio=1.784,95%CI:1.172-2.715,P=0.007)as independent predictors.The area under the curve for age,RDW,and their combination was 0.798(95%CI:0.695-0.900),0.801(95%CI:0.692-0.911),and 0.858(95%CI:0.771-0.944),respectively,with bootstrapped validation confirming stability.Cut-off values of age≥60 years and RDW≥15.5%balanced sensitivity and specificity,increasing malignancy risk 15.3-fold and 22.6-fold,respectively.CONCLUSION Age and RDW are independent predictors of malignancy in PCNs,aiding in patient selection for advanced diagnostics and surgery.Larger,multicenter studies are needed to validate these findings. 展开更多
关键词 Age Pancreatic Cystic Neoplasms Malignancy Risk Clinical parameters benign cysts Laboratory parameters pancreatic cystic neoplasms pcns radiographic techniqueswith
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Orientation Parameters Estimation and Lens Distortion Correction for UAVs Photogrammetry with Non-metric Cameras
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作者 DENG Xingsheng GAO Yang ZHU Xu 《Journal of Geodesy and Geoinformation Science》 2025年第1期71-88,共18页
The estimation of orientation parameters and correction of lens distortion are crucial problems in the field of Unmanned Aerial Vehicles(UAVs)photogrammetry.In recent years,the utilization of UAVs for aerial photogram... The estimation of orientation parameters and correction of lens distortion are crucial problems in the field of Unmanned Aerial Vehicles(UAVs)photogrammetry.In recent years,the utilization of UAVs for aerial photogrammetry has witnessed a surge in popularity.Typically,UAVs are equipped with low-cost non-metric cameras and a Position and Orientation System(POS).Unfortunately,the Interior Orientation Parameters(IOPs)of the non-metric cameras are not fixed.Whether the lens distortions are large or small,they effect the image coordinates accordingly.Additionally,Inertial Measurement Units(IMUs)often have observation errors.To address these challenges and improve parameter estimation for UAVs Light Detection and Ranging(LiDAR)and photogrammetry,this paper analyzes the accuracy of POS observations obtained from Global Navigation Satellite System Real Time Kinematic(GNSS-RTK)and IMU data.A method that incorporates additional known conditions for parameter estimation,a series of algorithms to simultaneously solve for IOPs,Exterior Orientation Parameters(EOPs),and camera lens distortion correction parameters are proposed.Extensive experiments demonstrate that the coordinates measured by GNSS-RTK can be directly used as linear EOPs;however,angular EOP measurements from IMUs exhibit relatively large errors compared to adjustment results and require correction during the adjustment process.The IOPs of non-metric cameras vary slightly between images but need to be treated as unknown parameters in high precision applications.Furthermore,it is found that the Ebner systematic error model is sensitive to the choice of the magnification parameter of the photographic baseline length in images,it should be set as less than or equal to one third of the photographic baseline to ensure stable solutions. 展开更多
关键词 UAVs photogrammetry non-metric cameras Interior Orientation parameters(IOPs) Exterior Orientation parameters(EOPs) lens distortion correction
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Parameterized Littlewood-Paley Operators and Their Commutators on Two-Weight Grand Homogeneous Variable Herz-Morrey Spaces
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作者 Xijuan CHEN Wenwen TAO Guanghui LU 《Journal of Mathematical Research with Applications》 2025年第2期231-242,共12页
In this paper,the authors prove that the parameterized area integralμ_(Ω,S)^(ρ)and the parameterized Littlewood-Paley g_(δ)^(*)-functionμ_(Ω,δ)^(*,ρ)are bounded on two-weight grand homogeneous variable Herz-Mo... In this paper,the authors prove that the parameterized area integralμ_(Ω,S)^(ρ)and the parameterized Littlewood-Paley g_(δ)^(*)-functionμ_(Ω,δ)^(*,ρ)are bounded on two-weight grand homogeneous variable Herz-Morrey spaces MK_(p),θ,q(·))^(α(·),λ)(ω_(1),ω_(2)),where θ>0,λ∈(2,∞),q(·)∈B(R^(n)),α(·)∈L^(∞)(R^(n)),ω_(1)∈A_(p_(ω_(1)))for p_(ω_(1))∈[1,∞]and ω_(2) is a weight.Furthermore,the authors prove that the commutators[b,μ_(Ω,S)^(ρ)]which is formed by b∈BMO(R^(n))and the μ_(Ω,S)^(ρ),and the[b,μ_(Ω,δ)^(*,ρ)]generated by b∈BMO(R^(n))and theμ_(Ω,δ)^(*,ρ)are bounded on MK_(p),θ,q(·))^(α(·),λ)(ω_(1),ω_(2)),respectively. 展开更多
关键词 Grand homogeneous variable Herz-Morrey space parameterized area integral parameterized Littlewood-Paley g_(δ)^(*)-function commutator space BMO(R^(n))
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Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations:A Review 被引量:5
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作者 Chao Zhang Shang-Xi Lai Hua-Ping Wang 《Structural Durability & Health Monitoring》 EI 2025年第1期25-54,共30页
Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters accordi... Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientific basis for structural damage identification and dynamic model modification.In view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and briefly describes how to identify structural damages based on the derived modal parameters.The paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),briefly describes damage identification methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artificial intelligence(AI)methods in the direction of modal parameter recognition and damage identification is further discussed.Based on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identification methods are given to provide scientific references for the optimized design and functional upgrading of SHM systems. 展开更多
关键词 Structural health monitoring data information modal parameters damage identification AI method
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Shear behaviors of intermittent joints subjected to shearing cycles under constant normal stiffness conditions:Effects of loading parameters 被引量:1
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作者 Bin Wang Yujing Jiang +1 位作者 Qiangyong Zhang Hongbin Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期2695-2712,共18页
A conceptual model of intermittent joints is introduced to the cyclic shear test in the laboratory to explore the effects of loading parameters on its shear behavior under cyclic shear loading.The results show that th... A conceptual model of intermittent joints is introduced to the cyclic shear test in the laboratory to explore the effects of loading parameters on its shear behavior under cyclic shear loading.The results show that the loading parameters(initial normal stress,normal stiffness,and shear velocity)determine propagation paths of the wing and secondary cracks in rock bridges during the initial shear cycle,creating different morphologies of macroscopic step-path rupture surfaces and asperities on them.The differences in stress state and rupture surface induce different cyclic shear responses.It shows that high initial normal stress accelerates asperity degradation,raises shear resistance,and promotes compression of intermittent joints.In addition,high normal stiffness provides higher normal stress and shear resistance during the initial cycles and inhibits the dilation and compression of intermittent joints.High shear velocity results in a higher shear resistance,greater dilation,and greater compression.Finally,shear strength is most sensitive to initial normal stress,followed by shear velocity and normal stiffness.Moreover,average dilation angle is most sensitive to initial normal stress,followed by normal stiffness and shear velocity.During the shear cycles,frictional coefficient is affected by asperity degradation,backfilling of rock debris,and frictional area,exhibiting a non-monotonic behavior. 展开更多
关键词 Intermittent joint Cyclic shear Loading parameter Constant normal stiffness(CNS)
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Parameter optimization of the observation system for the South Yellow Sea strong shielding layer based on seismic illumination analysis 被引量:1
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作者 Yang Jia-Jia Chen Jian-Wen +5 位作者 Huang Fu-Qiang Yan Zhong-Hui Lei Bao-Hua Wang Xiao-Jie Xu Hua-Ning Liu Hong 《Applied Geophysics》 2025年第1期84-98,233,共16页
The seismic data of the Laoshan Uplift in the South Yellow Sea Basin reveal a low signal-tonoise ratio and low refl ection signal energy in the deep Mesozoic–Paleozoic strata.The main reason is that the Mesozoic-Pale... The seismic data of the Laoshan Uplift in the South Yellow Sea Basin reveal a low signal-tonoise ratio and low refl ection signal energy in the deep Mesozoic–Paleozoic strata.The main reason is that the Mesozoic-Paleozoic marine carbonate rock strata are directly covered by the Cenozoic terrestrial clastic rock strata,which form a strong shielding layer.To obtain the reflection signals of the strata below the strong shielding layer,a one-way wave equation bidirectional illumination analysis of the main observation system parameters was conducted by analyzing the mechanism of the strong shielding layer.Low-frequency seismic sources are assumed to have a high illumination intensity on the reflection layer below the strong shielding layer.Accordingly,optimized acquisition parameter suggestions were proposed,and reacquisition was performed at the existing survey line locations in the Laoshan Uplift area.The imaging of the newly acquired data in the middle and deep layers was drastically improved.It revealed the unconformity between the Sinian and Cambrian under the strong shielding layer.The study yielded new insights into the tectonic and sedimentary evolution of the Lower Paleozoic in the South Yellow Sea. 展开更多
关键词 illumination analysis acquisition parameters Laoshan Uplift strong shielding layer
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Geometric parameter identification of bridge precast box girder sections based on deep learning and computer vision 被引量:1
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作者 JIA Jingwei NI Youhao +2 位作者 MAO Jianxiao XU Yinfei WANG Hao 《Journal of Southeast University(English Edition)》 2025年第3期278-285,共8页
To overcome the limitations of low efficiency and reliance on manual processes in the measurement of geometric parameters for bridge prefabricated components,a method based on deep learning and computer vision is deve... To overcome the limitations of low efficiency and reliance on manual processes in the measurement of geometric parameters for bridge prefabricated components,a method based on deep learning and computer vision is developed to identify the geometric parameters.The study utilizes a common precast element for highway bridges as the research subject.First,edge feature points of the bridge component section are extracted from images of the precast component cross-sections by combining the Canny operator with mathematical morphology.Subsequently,a deep learning model is developed to identify the geometric parameters of the precast components using the extracted edge coordinates from the images as input and the predefined control parameters of the bridge section as output.A dataset is generated by varying the control parameters and noise levels for model training.Finally,field measurements are conducted to validate the accuracy of the developed method.The results indicate that the developed method effectively identifies the geometric parameters of bridge precast components,with an error rate maintained within 5%. 展开更多
关键词 bridge precast components section geometry parameters size identification computer vision deep learning
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Multi-objective optimization of grinding process parameters for improving gear machining precision 被引量:1
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作者 YOU Tong-fei HAN Jiang +4 位作者 TIAN Xiao-qing TANG Jian-ping LU Yi-guo LI Guang-hui XIA Lian 《Journal of Central South University》 2025年第2期538-551,共14页
The gears of new energy vehicles are required to withstand higher rotational speeds and greater loads,which puts forward higher precision essentials for gear manufacturing.However,machining process parameters can caus... The gears of new energy vehicles are required to withstand higher rotational speeds and greater loads,which puts forward higher precision essentials for gear manufacturing.However,machining process parameters can cause changes in cutting force/heat,resulting in affecting gear machining precision.Therefore,this paper studies the effect of different process parameters on gear machining precision.A multi-objective optimization model is established for the relationship between process parameters and tooth surface deviations,tooth profile deviations,and tooth lead deviations through the cutting speed,feed rate,and cutting depth of the worm wheel gear grinding machine.The response surface method(RSM)is used for experimental design,and the corresponding experimental results and optimal process parameters are obtained.Subsequently,gray relational analysis-principal component analysis(GRA-PCA),particle swarm optimization(PSO),and genetic algorithm-particle swarm optimization(GA-PSO)methods are used to analyze the experimental results and obtain different optimal process parameters.The results show that optimal process parameters obtained by the GRA-PCA,PSO,and GA-PSO methods improve the gear machining precision.Moreover,the gear machining precision obtained by GA-PSO is superior to other methods. 展开更多
关键词 worm wheel gear grinding machine gear machining precision machining process parameters multi objective optimization
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Solid Waste Management:A MADM Approach Using Fuzzy Parameterized Possibility Single-Valued Neutrosophic Hypersoft Expert Settings
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作者 Tmader Alballa Muhammad Ihsan +2 位作者 Atiqe Ur Rahman Noorah Ayed Alsorayea Hamiden Abd El-Wahed Khalifa 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期531-553,共23页
The dramatic rise in the number of people living in cities has made many environmental and social problems worse.The search for a productive method for disposing of solid waste is the most notable of these problems.Ma... The dramatic rise in the number of people living in cities has made many environmental and social problems worse.The search for a productive method for disposing of solid waste is the most notable of these problems.Many scholars have referred to it as a fuzzy multi-attribute or multi-criteria decision-making problem using various fuzzy set-like approaches because of the inclusion of criteria and anticipated ambiguity.The goal of the current study is to use an innovative methodology to address the expected uncertainties in the problem of solid waste site selection.The characteristics(or sub-attributes)that decision-makers select and the degree of approximation they accept for various options can both be indicators of these uncertainties.To tackle these problems,a novel mathematical structure known as the fuzzy parameterized possibility single valued neutrosophic hypersoft expert set(ρˆ-set),which is initially described,is integrated with a modified version of Sanchez’s method.Following this,an intelligent algorithm is suggested.The steps of the suggested algorithm are explained with an example that explains itself.The compatibility of solid waste management sites and systems is discussed,and rankings are established along with detailed justifications for their viability.This study’s strengths lie in its application of fuzzy parameterization and possibility grading to effectively handle the uncertainties embodied in the parameters’nature and alternative approximations,respectively.It uses specific mathematical formulations to compute the fuzzy parameterized degrees and possibility grades that are missing from the prior literature.It is simpler for the decisionmakers to look at each option separately because the decision is uncertain.Comparing the computed results,it is discovered that they are consistent and dependable because of their preferred properties. 展开更多
关键词 Hypersoft expert set Sanchez’s method decision making optimization solid waste management possibility grade fuzzy parameterization
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Influence of Process Parameters on Forming Quality of Single-Channel Multilayer by Joule Heat Fuse Additive Manufacturing
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作者 Li Suli Fan Longfei +3 位作者 Chen Jichao Gao Zhuang Xiong Jie Yang Laixia 《稀有金属材料与工程》 北大核心 2025年第5期1165-1176,共12页
To overcome the shortage of complex equipment,large volume,and high energy consumption in space capsule manufacturing,a novel sliding pressure Joule heat fuse additive manufacturing technique with reduced volume and l... To overcome the shortage of complex equipment,large volume,and high energy consumption in space capsule manufacturing,a novel sliding pressure Joule heat fuse additive manufacturing technique with reduced volume and low energy consumption was proposed.But the unreasonable process parameters may lead to the inferior consistency of the forming quality of single-channel multilayer in Joule heat additive manufacturing process,and it is difficult to reach the condition for forming thinwalled parts.Orthogonal experiments were designed to fabricate single-channel multilayer samples with varying numbers of layers,and their forming quality was evaluated.The influence of printing current,forming speed,and contact pressure on the forming quality of the single-channel multilayer was analyzed.The optimal process parameters were obtained and the quality characterization of the experiment results was conducted.Results show that the printing current has the most significant influence on the forming quality of the single-channel multilayer.Under the optimal process parameters,the forming section is well fused and the surface is continuously smooth.The surface roughness of a single-channel 3-layer sample is 0.16μm,and the average Vickers hardness of cross section fusion zone is 317 HV,which lays a foundation for the subsequent use of Joule heat additive manufacturing technique to form thinwall parts. 展开更多
关键词 Joule heat additive manufacturing single-channel multilayer process parameter forming quality
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An identification model for weak influence parameters of nuclear power unit based on parameter recursion
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作者 LIANG Qian-Yun XU Xin 《四川大学学报(自然科学版)》 北大核心 2025年第4期986-991,共6页
In complex systems,there is a kind of parameters having only a minor impact on the outputs in most cases,but their accurate values are still critical for the operation of systems.In this paper,the authors focus on the... In complex systems,there is a kind of parameters having only a minor impact on the outputs in most cases,but their accurate values are still critical for the operation of systems.In this paper,the authors focus on the identification of these weak influence parameters in the complex systems and propose a identification model based on the parameter recursion.As an application,three parameters of the steam generator are identified,that is,the valve opening,the valve CV value,and the reference water level,in which the valve opening and the reference water level are weak influence parameters under most operating conditions.Numerical simulation results show that,in comparison with the multi-layer perceptron(MLP),the identification error rate is decreased.Actually,the average identification error rate for the valve opening decreases by 0.96%,for the valve CV decreases by 0.002%,and for the reference water level decreases by 12%after one recursion.After two recursions,the average identification error rate for the valve opening decreases by 11.07%,for the valve CV decreases by 2.601%,and for the reference water level decreases by 95.79%.This method can help to improve the control of the steam generator. 展开更多
关键词 Steam generator Nuclear power parameter identification Multi-layer perceptron
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Improvement of Lattice Parameter Accuracy in Single Crystal XRD Based on a Laser-Induced X-Ray Source
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作者 LIU Jin WANG Qiannan LI Jiangtao 《高压物理学报》 北大核心 2025年第4期9-15,共7页
The lattice parameter,measured with sufficient accuracy,can be utilized to evaluate the quality of single crystals and to determine the equation of state for materials.We propose an iterative method for obtaining more... The lattice parameter,measured with sufficient accuracy,can be utilized to evaluate the quality of single crystals and to determine the equation of state for materials.We propose an iterative method for obtaining more precise lattice parameters using the interaction points for the pseudo-Kossel pattern obtained from laser-induced X-ray diffraction(XRD).This method has been validated by the analysis of an XRD experiment conducted on iron single crystals.Furthermore,the method was used to calculate the compression ratio and rotated angle of an LiF sample under high pressure loading.This technique provides a robust tool for in-situ characterization of structural changes in single crystals under extreme conditions.It has significant implications for studying the equation of state and phase transitions. 展开更多
关键词 lattice parameter measurement accuracy single crystal X-ray diffraction iterative algorithm high pressure ratio of compression
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