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Magnetic Anomaly Interpretation of the Northern Congo Craton Boundary: Results from Depth Estimation and 2.5D Modeling
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作者 Basseka Charles Antoine Eyike Yomba Albert +3 位作者 Kenfack Jean Victor Njiteu Tchoukeu Cyrille Donald Som Mbang Constantin Mathieu Shandini Njankouo Yves 《Journal of Geoscience and Environment Protection》 2017年第12期90-101,共12页
A magnetic-based geophysical study was performed across the southern part of Cameroon to investigate the boundary between the Archean Congo craton and the Pan-African metamorphic belt. Magnetic gradient techniques inc... A magnetic-based geophysical study was performed across the southern part of Cameroon to investigate the boundary between the Archean Congo craton and the Pan-African metamorphic belt. Magnetic gradient techniques including Euler deconvolution and Tilt derivative have been applied to an aeromagnetic data profile to determine the depth of sources and their lateral extension. 2.5D magnetic modeling shows that the prominent magnetic positive anomalies observed on total magnetic map of south Cameroon are produced by deep and strongly magnetic bodies under the Pan-African formations mainly an important dyke formation structure with a high susceptibility of 0.041 (SI units), at an average depth of 4148 m and with a lateral extension of about 10 km. These bodies are interpreted to have emplaced at high crustal levels in a continental collision zone and were subsequently metamorphosed at granulite grade conditions, during the Pan-African orogeny about 620 Ma ago. 展开更多
关键词 CONGO CRATON Magnetic Anomalies EULER DECONVOLUTION TILT Derivative 2.5d modelING
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2.5D Modelling of Aeromagnetic Data and their Mining Implications over the Ngaoundere Area (Adamawa Province, Cameroon)
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作者 Meying Arsène Gouet Daniel Hervé +2 位作者 Ndougsa Mbarga Theophile Ndam Njikam Mouhamed Owono Amougou Olivier Ulrich Igor 《International Journal of Geosciences》 2019年第2期173-192,共20页
This study is based on the analysis and interpretation of aeromagnetic data using version 8.4 of the Geosoft Oasis Montaj Software, to map the subsurface or deep geological structures that affected the geological form... This study is based on the analysis and interpretation of aeromagnetic data using version 8.4 of the Geosoft Oasis Montaj Software, to map the subsurface or deep geological structures that affected the geological formations of the Ngaoundere area. The use of the standard aeromagnetic methods made it possible to draw up the maps of the residual magnetic field reduced to the equator (RTE), the horizontal gradient (HG), the analytical signal (AS) and that of the Euler solutions (ED) to find the main magnetic facies corresponding to these structures. The geological formations of the studied area thus appear to be intensely fractured by a NE-SW (N45°E) and ENE-WSW (N70°E) main orientation fault system, the depth of which has been estimated by combining the three-analytical methods HG, AS and ED. Advanced magmatic map analysis revealed dikes associated with vertical faults in the studied area. The development of an interpretative geological map taking into account the basic geology, the deep faults, the identified dikes and the mineralization index made it possible to extract a correlation between geological structures and mineralization of the studied area. The 2.5D modelling of two magnetic profiles plotted on the reduced residual map at the equator was performed to approximate the geometry and depth of the dikes sector, which are potential sources of mineralization here. 展开更多
关键词 AEROMAGNETIC Data ANALYTICAL Methods FAULTS MINERALIZATION 2.5d modelLING
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Quantitative Interpretation of Gravity Anomalies in the Kribi-Campo Sedimentary Basin (South Cameroon) Based on Spectral Analysis and 2.5D Modelling: Structural Implications
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作者 Kue Petou Rokis Malquaire Owona Angue Marie Louise Clotilde +5 位作者 Njingti Nfor Eloundou Essama Lionel Mioumnde Arthur Paterne Kue Negham Martine Clémence Manguelle-Dicoum Eliezer Weiqi Song 《Open Journal of Earthquake Research》 2020年第3期240-254,共15页
Ground gravity survey was recently carried out in the Lolabe-Campo area, which constitutes the southern onshore portion of the Kribi-Campo sub-basin in South Cameroon. The obtained gravity data were processed and inte... Ground gravity survey was recently carried out in the Lolabe-Campo area, which constitutes the southern onshore portion of the Kribi-Campo sub-basin in South Cameroon. The obtained gravity data were processed and interpreted in order to elucidate the subsurface geology of the area in which preliminary studies highlighted the presence of an intrusive igneous body. In order to determine the nature and the characteristics of this body, spectral analysis, ideal body solution and 2.5D modelling methods were applied to the gravity data. The results suggest that the emplacement, breaking up and separation of the intrusive igneous body were the outcome of two tectonic events corresponding to an upward vertical translational tectonic movement followed by an anticlockwise rotational faulting tectonic movement. From a density contrast of 0.13 g&#183cm&#453, the two isolated bodies have an estimated density of 2.80 g&#183cm&#453 which is comparatively higher than the average density of 2.67 g&#183cm&#453 of the autochthonous rocks. These two blocks are completely surrounded by both sedimentary and metamorphic formations and are confined between the depths of 0.6 km and 3.5 km. The highly dense nature of the rocks and their location around the Atlantic Ocean led to the conclusion that the two intrusive bodies are composed principally of gabbro. The disposition and shape of the open zone resulting from the separation of the blocks are suggestive of a trap for the accumulation of hydrocarbons and mineral resources. 展开更多
关键词 Spectral Analysis IDEAL Body 2.5d modelLING Formation Depth INTRUSIVE BLOCKS
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Description and Evaluation of the Emission and Atmospheric Processes Integrated and Coupled Community(EPICC)Model Version 1.0 被引量:1
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作者 EPICC Model Working Group 《Advances in Atmospheric Sciences》 2026年第4期671-694,I0001-I0006,共30页
We present a comprehensive description and benchmark evaluation of the global–regional chemical transport model called the Emission and Atmospheric Processes Integrated and Coupled Community(EPICC)model.The framework... We present a comprehensive description and benchmark evaluation of the global–regional chemical transport model called the Emission and Atmospheric Processes Integrated and Coupled Community(EPICC)model.The framework incorporates(1)grid configuration,(2)transport dynamics,(3)chemical mechanisms,(4)aerosol processes,(5)wet/dry deposition parameterizations,and(6)heterogeneous chemistry treatments associated with sulfate,nitrous acid(HONO)chemistry,and aerosol/cloud–photolysis interactions(APIs/CPIs).Openly shared with the atmospheric research community,the model facilitates integration of advanced physicochemical schemes to enhance simulation accuracy.Globally,the model demonstrates realistic representations of ozone(O_(3))and aerosol optical depth.The EPICC model generally demonstrates robust performance in simulating regional concentrations of O_(3) and PM_(2.5)(and its components)in China.It successfully captures vertical profiles of both global and regional O_(3).Notably,the model mitigates frequently reported sulfate underestimations in highly industrialized regions of China.The model accurately captures two regional severe pollution episodes observed in eastern China(January/June 2021).Sensitivity experiments highlight the critical roles of heterogeneous chemical mechanisms associated with sulfate,HONO chemistry,APIs,and CPIs in capturing PM_(2.5) and O_(3) concentrations in China.Improved sulfate mechanisms result in an increase of approximately 32.4%(2.8μg m^(−3))in simulated winter sulfate concentrations when observations exceed 10μg m^(−3).Enhanced HONO elevates winter O_(3) and PM_(2.5) by≤20 and≤10μg m^(−3),respectively.Overall,CPIs dominate over APIs in improving O_(3) and PM_(2.5) simulations across China.Locally,APIs mitigate PM_(2.5) and O_(3) discrepancies in the Sichuan Basin.Seasonal cloud–chemistry coupling explains the weaker impact of PM_(2.5) in summer. 展开更多
关键词 EPICC model PM_(2.5) O_(3) sulfate nitrous acid aerosol/cloud-photolysis interactions
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高性能纤维2.5D编织预制体密度设计方法
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作者 董经经 荆云娟 +3 位作者 韦鑫 张欢 杨燕宁 尉寄望 《化工新型材料》 北大核心 2026年第4期139-143,147,共6页
高性能纤维2.5D编织预制体是先进复合材料的结构增强相。高性能纤维的可织性反映了高性能纤维在织造成形加工过程中的抗损伤能力,其优劣直接影响织造效率和最终复材制品的性能和质量。合理设计高性能纤维2.5D编织预制体的密度是纤维可... 高性能纤维2.5D编织预制体是先进复合材料的结构增强相。高性能纤维的可织性反映了高性能纤维在织造成形加工过程中的抗损伤能力,其优劣直接影响织造效率和最终复材制品的性能和质量。合理设计高性能纤维2.5D编织预制体的密度是纤维可织性的前提。以2.5D浅交弯联结构为例,建立纤维束与其他接触部件的几何形态,根据纤维不同几何形态推出经纱密度与纬纱密度,进一步阐述了预制体的经纬向紧度、总紧度,对高性能纤维的编织难度进行评估,进而优化2.5D编织预制体的密度。 展开更多
关键词 高性能纤维 2.5d结构 密度 几何形态 紧度
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Recent Advances and Prospects in Research of In Vitro 3D Functional Skin Tissue Models
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作者 Li Tao Zhang Liqing 《China Detergent & Cosmetics》 2026年第1期75-88,共14页
With the increasing demand for understanding skin physiology and advancing regenerative medicine,in vitro three-dimensional(3D)functional skin tissue models have become vital tools in dermatological research.These mod... With the increasing demand for understanding skin physiology and advancing regenerative medicine,in vitro three-dimensional(3D)functional skin tissue models have become vital tools in dermatological research.These models effectively mimic the complex structure and functions of human skin.This review comprehensively discusses the latest advancements in construction techniques,material selection,and applications of 3D skin models.It highlights the advantages and challenges associated with cutting-edge technologies such as layer-by-layer cell coating,3D bioprinting,bio-spray technology,and photolithographic microfabrication in creating highly realistic skin models.Moreover,it examines the wide-ranging applications of 3D skin models,includingelucidation of skin disease mechanisms,investigation of skin barrier functions,studies on skin aging and repair,hair regeneration,efficacy screening of therapeutic agents,cosmetic safety assessment,and personalized medicine.Finally,this review anticipates future trends in developing 3D skin models with greater structural and functional complexity,enhanced multifunctionality,and improved clinical translation. 展开更多
关键词 3D skin models tissue engineering BIOPRINTING skin barrier disease modeling drug screening hair regeneration skin aging
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Bioengineered intestinal models:structural precision drives functional and microbial fidelity
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作者 Ziqi Gao Huilong Du +7 位作者 Shuyuan Yu Qi Li Yang Li Jun Yin Huayong Yang Yue Wang Hongzhao Zhou Luqi Shen 《Bio-Design and Manufacturing》 2026年第2期240-265,I0004,共27页
The intestine is a key component of the barrier,absorption,and immune systems,contributing significantly to maintaining internal homeostasis and influencing disease progression.Its distinctive physiological functions ... The intestine is a key component of the barrier,absorption,and immune systems,contributing significantly to maintaining internal homeostasis and influencing disease progression.Its distinctive physiological functions arise from a complex interplay between its structure and microenvironment.Recent advancements in bioengineering technologies now enable the construction of in vitro intestinal models that faithfully recapitulate the organizational and functional characteristics of native tissue.This review examines the interface between in vitro models and native intestinal biology,offering insights into the replication of organ functions from a manufacturing perspective.We explore bioengineering strategies that enable the mapping of cross-scale structures and the creation of biomimetic environments essential for physiological performance.Furthermore,we discuss pragmatic optimization strategies for applying these models to both physiological and pathological studies,thereby enhancing their translational potential for drug development,disease modeling,and personalized medicine.In contrast to previous reviews,this work proposes an engineering-centered framework for linking structural fabrication strategies to functional performance across intestinal model types. 展开更多
关键词 Intestinal model Organ-on-chip Organoid 3 D bioprinting Biomedical application
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Methods for a bioengineered 3D human brain-like tissue model of neuroregeneration after traumatic brain injury
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作者 Marly Coe Sydni Rosenfeld +2 位作者 Celia Byrne Volha Liaudanskaya David L.Kaplan 《Neural Regeneration Research》 2026年第8期3620-3628,共9页
Traumatic brain injury causes permanent cell death and can lead to long-term cognitive dysfunction,with no available treatments to repair the damaged brain tissue.Methods to track and understand traumatic brain injury... Traumatic brain injury causes permanent cell death and can lead to long-term cognitive dysfunction,with no available treatments to repair the damaged brain tissue.Methods to track and understand traumatic brain injury in humans are severely limited by the inaccessibility of living brain tissue,creating a need for in vitro model systems to study cellular mechanisms of degeneration and regeneration following injury.Here we describe methods to establish a 3D human brain tissue model,consisting of a silk-collagen composite scaffold seeded with human neurons,astrocytes,and microglia,to study neuro-regeneration after traumatic brain injury.Step-by-step fabrication,injury,and analytical assessments of the 3D“triculture”system are described.Using this tissue model system,we demonstrate that glial cells promote regeneration of neuronal networks within the injury site over several weeks post-injury.Further,we found that regenerating networks in the 3D triculture tissues did not secrete early markers of neurodegenerative disease,but displayed signs of excitatory/inhibitory imbalance,suggesting that pro-regenerative treatments for traumatic brain injury in the future may need to direct cell differentiation to promote proper function.The mechanical stability of this model system enables physiologically relevant impact injury and long-term culture capability,while its modular design enables modification of cell contents,extracellular matrix composition,and scaffold properties.This adaptability could allow the integration of patient-derived cells and genetic modifications to bridge research and clinical applications focused on personalized targeted therapies.This in vitro system provides a valuable platform for accelerating therapeutic advancements in traumatic brain injury and neurodegenerative disorders,ultimately improving patient outcomes. 展开更多
关键词 3D model EXCITOTOXICITY glial cells human brain in vitro model NEURODEGENERATION neuronal networks REGENERATION tissue engineering traumatic brain injury
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Delaminated lower slab thermal regime before slab break-off in the Pamirs:Implications from 3D kinematic modeling
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作者 Haris Faheem YingFeng Ji +6 位作者 Waqar Ahmed Rui Qu Ye Zhu Fitriani Fitriani Jun Yang Shoichi Yoshioka Nobuaki Suenaga 《Earth and Planetary Physics》 2026年第1期13-21,共9页
The intracontinental subduction of a>200-km-long section of the Tajik-Tarim lithosphere beneath the Pamir Mountains is proposed to explain nearly 30 km of shortening in the Tajik fold-thrust belt and the Pamir upli... The intracontinental subduction of a>200-km-long section of the Tajik-Tarim lithosphere beneath the Pamir Mountains is proposed to explain nearly 30 km of shortening in the Tajik fold-thrust belt and the Pamir uplift.Seismic imaging revealed that the upper slab was scraped and that the lower slab had subducted to a depth of>150 km.These features constitute the tectonic complexity of the Pamirs,as well as the thermal subduction mechanism involved,which remains poorly understood.Hence,in this study,high-resolution three-dimensional(3D)kinematic modeling is applied to investigate the thermal structure and geometry of the subducting slab beneath the Pamirs.The modeled slab configuration reveals distinct along-strike variations,with a steeply dipping slab beneath the southern Pamirs,a more gently inclined slab beneath the northern Pamirs,and apparent upper slab termination at shallow depths beneath the Pamirs.The thermal field reveals a cold slab core after delamination,with temperatures ranging from 400℃to 800℃,enveloped by a hotter mantle reaching~1400℃.The occurrence of intermediate-depth earthquakes aligns primarily with colder slab regions,particularly near the slab tear-off below the southwestern Pamirs,indicating a strong correlation between slab temperature and seismicity.In contrast,the northern Pamirs exhibit reduced seismicity at depth,which is likely associated with thermal weakening and delamination.The central Pamirs show a significant thermal anomaly caused by a concave slab,where the coldest crust does not descend deeply,further suggesting crustal detachment or mechanical failure.The lateral asymmetry in slab temperature possibly explains the mechanism of lateral tearing and differential slab-mantle coupling. 展开更多
关键词 PAMIRS SUBDUCTION 3D kinematic modeling slab geometry intermediate-depth earthquake crustal delamination seismicity distribution
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Automatic gating and riser system design and defect control for K4169 superalloy guide blade casting based on parametric 3D modeling-simulation integrated system
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作者 Le-chuan Li Ya-jun Yin +4 位作者 Bing-zheng Fan Guo-yan Shui Xiao-yuan Ji Jian-xin Zhou Lei Jin 《China Foundry》 2026年第1期20-30,共11页
Automation and intelligence have become the primary trends in the design of investment casting processes.However,the design of gating and riser systems still lacks precise quantitative evaluation criteria.Numerical si... Automation and intelligence have become the primary trends in the design of investment casting processes.However,the design of gating and riser systems still lacks precise quantitative evaluation criteria.Numerical simulation plays a significant role in quantitatively evaluating current processes and making targeted improvements,but its limitations lie in the inability to dynamically reflect the formation outcomes of castings under varying process conditions,making real-time adjustments to gating and riser designs challenging.In this study,an automated design model for gating and riser systems based on integrated parametric 3D modeling-simulation framework is proposed,which enhances the flexibility and usability of evaluating the casting process by simulation.Firstly,geometric feature extraction technology is employed to obtain the geometric information of the target casting.Based on this information,an automated design framework for gating and riser systems is established,incorporating multiple structural parameters for real-time process control.Subsequently,the simulation results for various structural parameters are analyzed,and the influence of these parameters on casting formation is thoroughly investigated.Finally,the optimal design scheme is generated and validated through experimental verification.Simulation analysis and experimental results show that using a larger gate neck(24 mm in side length) and external risers promotes a more uniform temperature distribution and a more stable flow state,effectively eliminating shrinkage cavities and enhancing process yield by 15%. 展开更多
关键词 numerical simulation automatic design investment casting parametric 3D modeling gating and riser system
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Development of Patient-Derived Conditionally Reprogrammed 3D Breast Cancer Culture Models for Drug Sensitivity Evaluation
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作者 Jing Cai Haoyun Zhu +4 位作者 Weiling Guo Ting Huang Pangzhou Chen Wen Zhou Ziyun Guan 《Oncology Research》 2026年第1期500-520,共21页
Background:Therapeutic responses of breast cancer vary among patients and lead to drug resistance and recurrence due to the heterogeneity.Current preclinical models,however,are inadequate for predicting individual pat... Background:Therapeutic responses of breast cancer vary among patients and lead to drug resistance and recurrence due to the heterogeneity.Current preclinical models,however,are inadequate for predicting individual patient responses towards different drugs.This study aimed to investigate the patient-derived breast cancer culture models for drug sensitivity evaluations.Methods:Tumor and adjacent tissues from female breast cancer patients were collected during surgery.Patient-derived breast cancer cells were cultured using the conditional reprogramming technique to establish 2D models.The obtained patient-derived conditional reprogramming breast cancer(CRBC)cells were subsequently embedded in alginate-gelatin methacryloyl hydrogel microspheres to form 3D culture models.Comparisons between 2D and 3D models were made using immunohistochemistry(tumor markers),MTS assays(cell viability),flow cytometry(apoptosis),transwell assays(migration),and Western blotting(protein expression).Drug sensitivity tests were conducted to evaluate patient-specific responses to anti-cancer agents.Results:2D and 3D culture models were successfully established using samples from eight patients.The 3D models retained histological and marker characteristics of the original tumors.Compared to 2D cultures,3D models exhibited increased apoptosis,enhanced drug resistance,elevated stem cell marker expression,and greater migration ability—features more reflective of in vivo tumor behavior.Conclusion:Patient-derived 3D CRBC models effectively mimic the in vivo tumor microenvironment and demonstrate stronger resistance to anti-cancer drugs than 2D models.These hydrogel-based models offer a cost-effective and clinically relevant platform for drug screening and personalized breast cancer treatment. 展开更多
关键词 Patient-derived breast cancer cells conditional reprogramming hydrogel microsphere 3D culture model drug screening
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Motion In-Betweening via Frequency-Domain Diffusion Model
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作者 Qiang Zhang Shuo Feng +2 位作者 Shanxiong Chen Teng Wan Ying Qi 《Computers, Materials & Continua》 2026年第1期275-296,共22页
Human motion modeling is a core technology in computer animation,game development,and humancomputer interaction.In particular,generating natural and coherent in-between motion using only the initial and terminal frame... Human motion modeling is a core technology in computer animation,game development,and humancomputer interaction.In particular,generating natural and coherent in-between motion using only the initial and terminal frames remains a fundamental yet unresolved challenge.Existing methods typically rely on dense keyframe inputs or complex prior structures,making it difficult to balance motion quality and plausibility under conditions such as sparse constraints,long-term dependencies,and diverse motion styles.To address this,we propose a motion generation framework based on a frequency-domain diffusion model,which aims to better model complex motion distributions and enhance generation stability under sparse conditions.Our method maps motion sequences to the frequency domain via the Discrete Cosine Transform(DCT),enabling more effective modeling of low-frequency motion structures while suppressing high-frequency noise.A denoising network based on self-attention is introduced to capture long-range temporal dependencies and improve global structural awareness.Additionally,a multi-objective loss function is employed to jointly optimize motion smoothness,pose diversity,and anatomical consistency,enhancing the realism and physical plausibility of the generated sequences.Comparative experiments on the Human3.6M and LaFAN1 datasets demonstrate that our method outperforms state-of-the-art approaches across multiple performance metrics,showing stronger capabilities in generating intermediate motion frames.This research offers a new perspective and methodology for human motion generation and holds promise for applications in character animation,game development,and virtual interaction. 展开更多
关键词 Motion generation diffusion model frequency domain human motion synthesis self-attention network 3D motion interpolation
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From Algorithm to Expert:RLHF-Guided Vision-Language Model for 3D-EEM Fluorescence Spectroscopy Matching
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作者 Chenglong Lu Jiehui Li +5 位作者 Tonglin Chen Changhua Zhou Yixin Fan Xinlin Ren Ziyi Ju Wei Wang 《Computers, Materials & Continua》 2026年第5期1883-1900,共18页
Existing methods for tracing water pollution sources typically integrate three-dimensional excitationemission matrix(3D-EEM)fluorescence spectroscopy with similarity-based matching algorithms.However,these approaches ... Existing methods for tracing water pollution sources typically integrate three-dimensional excitationemission matrix(3D-EEM)fluorescence spectroscopy with similarity-based matching algorithms.However,these approaches exhibit high error rates in borderline cases and necessitate expert manual review,which limits scalability and introduces inconsistencies between algorithmic outputs and expert judgment.To address these limitations,we propose a large vision-language model(VLM)designed as an“expert agent”to automatically refine similarity scores,ensuring alignment with expert decisions and overcoming key application bottlenecks.The model consists of two core components:(1)rule-based similarity calculation module generate initial spectral similarity scores,and(2)pre-trained large vision-language model fine-tuned via supervised learning and reinforcement learning with human feedback(RLHF)to emulate expert assessments.To facilitate training and evaluation,we introduce two expert-annotated datasets,Spec1k and SpecReason,which capture both quantitative corrections and qualitative reasoning patterns,allowing the model to emulate expert decision-making processes.Experimental results demonstrate that our method achieves 81.45%source attribution accuracy,38.24%higher than rule-based and machine learning baselines.Real-world deployment further validates its effectiveness. 展开更多
关键词 Vision-language model reinforcement learning with human feedback pollution source tracing 3D fluorescence spectroscopy
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2.5D Crustal Models Derived from Analytical Polynomial Separation Technique and Spectral Analysis of Gravity Data with Their Probable Gold Mineralization Migrations (Batouri, SE-Cameroon) 被引量:1
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作者 Ngoumou Paul Claude Assembe Stephane Patrick +4 位作者 Owono Amougou Olivier Ulrich Igor Meying Arsene Yandjimaing Justine Ngoh Jean Daniel Pepogo Man-Mvele Augustin Didier 《Advances in Remote Sensing》 2021年第1期1-24,共24页
Geophysical surveying is crucial in the investigation of mineral resources in poorly exposed areas such as SE-Cameroon, a region known for its gold mineral potential. In this paper, gravity survey is carried out in th... Geophysical surveying is crucial in the investigation of mineral resources in poorly exposed areas such as SE-Cameroon, a region known for its gold mineral potential. In this paper, gravity survey is carried out in the Batouri area, SE-Cameroon based on land gravity data from the Centre-south Cameroon. <span style="font-family:Verdana;">Therefore, an analytical polynomial separation program, based on least-square fi</span><span style="font-family:Verdana;">tting of a third-degree polynomial surface to the Bouguer anomaly map, was used to separate the regional/residual components in gravity data. This technique permitted to better understand the disposition of the deep and near surface structures responsible of the observed anomalies in the Batouri area. Spectral analysis and 2.5D modelling of two profiles P</span><sub><span style="font-family:Verdana;">1</span></sub><span style="font-family:Verdana;"> (SW-NE) and P</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> (N-S) selected from the residual anomaly map provided depths to basement. These depths constrain the gravity models along the profiles, indicating a variable thickness of the sedimentary infill with an approximate anomaly of -</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">33 mGal. The 2.5D model of the basement shows a gravity body, with a signature suggesting two close and similar masses, which characterize the quartz-bearing formations associated here to granite and gneiss. Our work highlights a main heavy gravity: Gwé-Batouri anomaly, containing the major part of auriferous deposits located along the NE-SW direction. Further, three tectonic sub-basins bounded by normal faults have been highlighted at Guedal, Gwé, and Bélimban, in the south of Guedal-Bélimban depression. They are associated with the extension tectonics, more or less vertical tangential cuts and accidents that have affected the region. A correlation with previous results from tectonic, lithological and gold mineralization activities proves the relevance of the study and the need to intensify geophysical surveying in the area.</span></span></span> 展开更多
关键词 Gravity Anomaly SE-Cameroon Polynomial Technique Spectral Analysis 2.5d modelling Gold Mineralization Batouri Area
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2.5D forward modeling and inversion of frequency-domain airborne electromagnetic data 被引量:1
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作者 李文奔 曾昭发 +3 位作者 李静 陈雄 王坤 夏昭 《Applied Geophysics》 SCIE CSCD 2016年第1期37-47,218,共12页
Frequency-domain airborne electromagnetics is a proven geophysical exploration method.Presently,the interpretation is mainly based on resistivity-depth imaging and onedimensional layered inversion;nevertheless,it is d... Frequency-domain airborne electromagnetics is a proven geophysical exploration method.Presently,the interpretation is mainly based on resistivity-depth imaging and onedimensional layered inversion;nevertheless,it is difficult to obtain satisfactory results for two- or three-dimensional complex earth structures using 1D methods.3D forward modeling and inversion can be used but are hampered by computational limitations because of the large number of data.Thus,we developed a 2.5D frequency-domain airborne electromagnetic forward modeling and inversion algorithm.To eliminate the source singularities in the numerical simulations,we split the fields into primary and secondary fields.The primary fields are calculated using homogeneous or layered models with analytical solutions,and the secondary(scattered) fields are solved by the finite-element method.The linear system of equations is solved by using the large-scale sparse matrix parallel direct solver,which greatly improves the computational efficiency.The inversion algorithm was based on damping leastsquares and singular value decomposition and combined the pseudo forward modeling and reciprocity principle to compute the Jacobian matrix.Synthetic and field data were used to test the effectiveness of the proposed method. 展开更多
关键词 Frequency-domain airborne electromagnetic finite element method 2.5d geoelectric model damped least-squares method
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2.5D C_(f)/SiC复合材料与SiC陶瓷微磨削性能对比试验研究
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作者 巩亚东 李远峰 +1 位作者 温泉 任启震 《东北大学学报(自然科学版)》 北大核心 2025年第1期52-60,共9页
为探究2.5D C_(f)/SiC复合材料与SiC陶瓷的微尺度磨削过程,对比2种材料在同一工艺参数下表面显微形貌、表面粗糙度与磨削力的差异,并分析工艺参数变化对磨削性能评价参数的影响;采用直径为0.9 mm的500#电镀金刚石微磨具对2种材料分别进... 为探究2.5D C_(f)/SiC复合材料与SiC陶瓷的微尺度磨削过程,对比2种材料在同一工艺参数下表面显微形貌、表面粗糙度与磨削力的差异,并分析工艺参数变化对磨削性能评价参数的影响;采用直径为0.9 mm的500#电镀金刚石微磨具对2种材料分别进行单因素微磨削试验.结果表明,2.5D C_(f)/SiC复合材料去除过程不同于SiC陶瓷,这是因为复合材料增强纤维的存在,有效抑制了微磨削过程中裂纹的扩展;在同一工艺参数下,2.5D C_(f)/SiC复合材料表面微观形貌较好、缺陷少、表面粗糙度小,而无纤维增强的SiC陶瓷表面微观形貌较差、缺陷多、表面粗糙度大;SiC陶瓷的平均磨削力大于2.5D C_(f)/SiC,并且在微磨削过程中,2.5D C_(f)/SiC的实时磨削力信号较平稳,而SiC陶瓷的实时磨削力信号存在尖刺. 展开更多
关键词 2.5d C_(f)/SiC复合材料 SIC陶瓷 微磨削过程 表面微观形貌 表面粗糙度 磨削力
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2.5D封装冲击可靠性分析
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作者 周春燕 卢琰 《北京理工大学学报》 北大核心 2025年第7期703-710,共8页
2.5D封装凭借其异构集成和低成本的优势,成为下一代集成电路的重要发展方向.电子器件中约20%的故障源自冲击与振动,因此分析2.5D封装在跌落冲击下的动态特性具有重要意义.以某2.5D封装为例,采用ANSYS/LSDYNA结合Input-G方法,焊点采用线... 2.5D封装凭借其异构集成和低成本的优势,成为下一代集成电路的重要发展方向.电子器件中约20%的故障源自冲击与振动,因此分析2.5D封装在跌落冲击下的动态特性具有重要意义.以某2.5D封装为例,采用ANSYS/LSDYNA结合Input-G方法,焊点采用线弹性模型和应变率相关的Johnson-Cook本构模型,对2.5D封装的跌落冲击瞬态响应进行了仿真.引入下填充材料以提高焊点的可靠性,分析了加速度幅值和脉冲时间对焊点可靠性的影响.结果表明:Johnson-Cook本构模型的焊点应力小于线弹性模型,且增加下填充材料能极大提高焊点的可靠性,填充面积越大效果越好;同时,加速度幅值和脉冲时间增大会降低焊点的可靠性. 展开更多
关键词 2.5d封装 冲击 下填充 应变率效应
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基于硅转接板的2.5D封装中电源地平面研究和优化
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作者 陈龙 宋昌明 +3 位作者 周晟娟 章莱 王谦 蔡坚 《电子与封装》 2025年第11期34-40,共7页
针对基于硅转接板的2.5D封装中电源分配网络(PDN)阻抗大、系统电压噪声大的电源完整性问题,建立2.5D封装模型,研究和优化封装系统的电源完整性。采用三维电磁场与电路协同仿真的方法,对硅转接板上的电源地平面进行阻抗优化,并通过合理... 针对基于硅转接板的2.5D封装中电源分配网络(PDN)阻抗大、系统电压噪声大的电源完整性问题,建立2.5D封装模型,研究和优化封装系统的电源完整性。采用三维电磁场与电路协同仿真的方法,对硅转接板上的电源地平面进行阻抗优化,并通过合理选择与布局深槽电容(DTC)对系统进行阻抗优化和电压噪声改善。结果显示,提高电源地平面的布线密度能够有效降低PDN的阻抗。电源地平面线宽/线距存在优化下限,当线宽/线距小于片间互连信号线线宽的2倍时会对片间互连信号线产生阻抗不连续的不良影响。在所建立的模型中,根据PDN阻抗的高频谐振峰选择DTC,使得PDN阻抗降低约83%,电压噪声减小约42%。同时,DTC的集成会在中高频段引入新的谐振峰,对PDN产生阻抗增大的不利影响。 展开更多
关键词 2.5d封装 硅转接板 电源完整性 电源地平面 深槽电容
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2.5D C/SiC复合材料磁场/液体辅助皮秒激光制孔试验研究
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作者 刘畅 王科骄 李丞 《航空制造技术》 北大核心 2025年第1期54-63,共10页
2.5D C/SiC复合材料是航空国防领域耐高温构件用关键复合材料,其高硬度、高耐磨性使该材料的高质量微孔加工异常困难。本文提出了一种基于磁场/液体辅助(MLM)的2.5D C/SiC复合材料皮秒激光制孔工艺,通过提取微孔的出/入口直径、锥度、... 2.5D C/SiC复合材料是航空国防领域耐高温构件用关键复合材料,其高硬度、高耐磨性使该材料的高质量微孔加工异常困难。本文提出了一种基于磁场/液体辅助(MLM)的2.5D C/SiC复合材料皮秒激光制孔工艺,通过提取微孔的出/入口直径、锥度、氧化、重铸层等特征,与皮秒激光加工(PM)、磁场辅助加工(MM)、液体辅助加工(LM)3种工艺进行了对比研究。结果表明,基于MLM的皮秒激光加工能够有效降低微孔的入口直径,同时增大出口直径,在两组不同的试验参数下分别获得了锥度1.3°及1.1°的微孔,比PM工艺的锥度分别降低了18.75%和45%,比MM工艺的锥度分别降低了13.33%和31.25%,比LM工艺的锥度分别降低了91.22%和79.63%。此外,利用EDS能谱分析、拉曼光谱以及XPS技术对制备的微孔开展了微观组织分析。可以发现,MLM工艺更有效地减少了孔壁的石墨化缺陷。其中,液体辅助避免了微孔入口处的氧化,同时清晰地观察到裸露的纤维和基体,有效避免了热损伤和重铸层缺陷。在皮秒激光制孔中,MLM的主要作用机制体现在液体的冷却效应、隔绝氧气机制,以及磁场纵向拉伸等离子体,从而减弱等离子体屏蔽效应。 展开更多
关键词 皮秒激光 磁场/液体辅助加工 2.5d C/SiC复合材料 孔锥度 烧蚀机理
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Fatigue life prediction model of 2.5D woven composites at various temperatures 被引量:5
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作者 Jian SONG Weidong WEN Haitao CUI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第2期310-329,共20页
As one of the new structural layout in the family of woven composites, 2.5D Woven Composites(2.5D-WC) have recently attracted an increasing interest owing to its excellent properties, i.e. high specific strength and... As one of the new structural layout in the family of woven composites, 2.5D Woven Composites(2.5D-WC) have recently attracted an increasing interest owing to its excellent properties, i.e. high specific strength and fatigue resistance, in the aerospace and automobile industry. Indepth understanding of the fatigue behavior of this material at un-ambient temperatures is critical for the engineering applications, especially in aero-engine field. Here, fatigue behavior of 2.5D-WC at different temperatures was numerically investigated based on the unit cell approach. Firstly, the unit cell model of 2.5D-WC was established using ANSYS software. Subsequently, the temperature-dependent fatigue life prediction model was built up. Finally, the fatigue lives alongside the damage evolution processes of 2.5D-WC at ambient temperature(20 ℃) and unambient temperature(180 ℃) were analyzed. The results show that numerical results are in good agreement with the relevant experimental results at 20 and 180 ℃. Fatigue behavior of 2.5D-WC is also sensitive to temperature, which is partially attributed to the mechanical properties of resin and the change of inclination angle of warp yarns. We hope that the proposed fatigue life prediction model and the findings could further promote the engineering application of 2.5D-WC, especially in aero-engine field. 展开更多
关键词 ANSYS Fatigue behavior Fatigue life prediction model TEMPERATURE 2.5d woven composites
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