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Research on dynamic three-dimensional terrain correction methods of quantitative inversion for airborne gamma-ray spectrometer
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作者 He-Xi Wu Wei-Cheng Li +6 位作者 Rui Qiu Chao Xiong Yi-Ming Lyu Yi-Qiang Xing De-Hao Zhang Zong-Shuo Tao Yang Wang 《Nuclear Science and Techniques》 2026年第5期199-214,共16页
Aerial surveys are dynamic and continuous processes,and there are different height distributions of the ground in the measurement area,which leads to problems such as overlapping measurement areas and inaccurate altit... Aerial surveys are dynamic and continuous processes,and there are different height distributions of the ground in the measurement area,which leads to problems such as overlapping measurement areas and inaccurate altitude correction during the survey process.Commonly used terrain correction methods are based on the concept of finite elementization of ground surface radioactive sources,using GPS coordinates,radar altitude,and ground elevation distribution information from aerial surveys,combined with the sourceless efficiency calibration method to construct a response matrix,which is then inverted for surface nuclide content.However,most of the sourceless efficiency calibration methods used are numerical calculations that consider the body detector as a point detector and do not consider the changes in intrinsic detection efficiency under different incident directions of gamma rays.Therefore,when the altitude of the measurement area varies significantly or the flight altitude of the aerial survey is relatively low,such sourceless efficiency calibration method calculations tend to have a large bias,which affects the accuracy of the terrain correction.To address the above problems,this study employs a novel sourceless efficiency calibration method based on the Boolean operation of the ray deposition process and simplifies the traditional body source measurement model to a surface source measurement model to achieve fast and accurate efficiency calibration.Then,through the discretization of the measurement process,the static measurement process is superposed as equivalent to the dynamic measurement process,and the dynamic measurement response matrix is built and optimized based on the calibration method.Finally,the PSO-MLEM algorithm was used to solve the dynamic measurement response matrix to achieve dynamic terrain correction of aerial survey data.Analysis of the Baiyun'ebo test area revealed that,after applying dynamic terrain correction,the inverted anomalies in uranium(eU),thorium(eTh),and potassium(K)concentrations were closer to ground measurements(within 5.72%-30.79%)and exhibited clearer anomaly boundaries compared to traditional height-based corrections.However,owing to the inherent statistical fluctuations and characteristics of matrix inversion,higher measurement values tend to absorb lower ones,potentially enlarging the anomalous regions.Nevertheless,the highanomaly regions after inversion largely coincided with the ground truth validation,demonstrating that the proposed method can effectively correct airborne gamma spectrometry data. 展开更多
关键词 Airborne gamma-ray spectrum Dynamic three-dimensional Terrain correction
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Ecological Three-Dimensional Cultivation and Digital Development Model of Xinjiashan Specialty Coffee Base
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作者 Jiangnan WANG Yulian MA +3 位作者 Tingting YANG Caide DUAN Jin'e LI Guangxue YANG 《Plant Diseases and Pests》 2026年第1期22-25,29,共5页
Under the strategic framework of rural revitalization and agricultural modernization, Xinjiashan Specialty Coffee Base, located in Zaotang Village, Lujiang Town, Longyang District, Baoshan City, has been proactively i... Under the strategic framework of rural revitalization and agricultural modernization, Xinjiashan Specialty Coffee Base, located in Zaotang Village, Lujiang Town, Longyang District, Baoshan City, has been proactively investigating innovative models for agricultural development. Through extensive communication and collaboration, this base has established close partnerships with research institutions including Kunming University of Science and Technology, Baoshan University, and Yunnan Academy of Agricultural Sciences, with a commitment to thoroughly exploring the potential for resource recycling and ecological complementarity. An innovative four-in-one three-dimensional integrated planting system incorporating "coffee, bananas, green manure, and bees" has been implemented. Concurrently, technological and digital management strategies have been comprehensively integrated to improve planting efficiency. Under this model, the proportion of specialty coffee attains 71%, and the per-unit yield is 17% greater than that of the conventional planting model. This approach not only substantially enhances economic returns but also promotes the integrated development of ecological and social benefits, offering a valuable practical example and experiential reference for the specialty and sustainable advancement of the coffee industry in comparable regions. 展开更多
关键词 COFFEE three-dimensional planting DIGITALIZATION Ecological cycle Xinjiashan
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Accurate closed-form flutter eigensolutions of three-dimensional composite laminates with shear deformation
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作者 Dezhuang PAN Yufeng XING 《Chinese Journal of Aeronautics》 2026年第1期230-246,共17页
According to the Mindlin plate theory and the first-order piston theory,this work obtains accurate closed-form eigensolutions for the flutter problem of three-dimensional(3D)rectangular laminated panels.The governing ... According to the Mindlin plate theory and the first-order piston theory,this work obtains accurate closed-form eigensolutions for the flutter problem of three-dimensional(3D)rectangular laminated panels.The governing differential equations are derived by the Hamilton's variational principle,and then solved by the iterative Separation-of-Variable(i SOV)method,which are applicable to arbitrary combinations of homogeneous Boundary Conditions(BCs).However,only the simply-support,clamped and cantilever panels are considered in this work for the sake of clarity.With the closed-form eigensolutions,the flutter frequency,flutter mode and flutter boundary are presented,and the effect of shear deformation and aerodynamic damping on flutter frequencies is investigated.Besides,the relation between panel energy and the work of aerodynamic load is discussed.The numerical comparisons reveal the following.(A)The flutter eigenvalues obtained by the present method are accurate,validated by the Finite Element Method(FEM)and the Galerkin method.(B)When the span-chord ratio is larger than 3,simplifying a 3D panel to 2D(two-dimensional)panel is reasonable and the relative differences of the flutter points predicted by the two models are less than one percent.(C)The reciprocal relationship between the mechanical energy of the panel and the work done by aerodynamic load is verified by using the present flutter eigenvalues and modes,further indicating the high accuracy of the present solutions.(D)The coupling of shear deformation and aerodynamic damping prevents frequency coalescing. 展开更多
关键词 Closed-form eigensolutions The first-order piston theory The Mindlin plate theory three-dimensional panel flutter Separation-of-variable method
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Three-dimensional reconstruction under computed tomography and myopectineal orifice measurement under laparoscopy for quality control of inguinal hernia treatment 被引量:1
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作者 Lei Zhang Jing Chen +7 位作者 Yu-Ying Zhang Lei Liu Han-Dan Wang Ya-Fei Zhang Jun Sheng Qiu-Shi Hu Ming-Liang Liu Yi-Lin Yuan 《World Journal of Gastrointestinal Endoscopy》 2025年第3期50-59,共10页
BACKGROUND Inguinal hernias are common after surgery.Tension-free repair is widely accepted as the main method for managing inguinal hernias.Adequate exposure,coverage,and repair of the myopectineal orifice(MPO)are ne... BACKGROUND Inguinal hernias are common after surgery.Tension-free repair is widely accepted as the main method for managing inguinal hernias.Adequate exposure,coverage,and repair of the myopectineal orifice(MPO)are necessary.However,due to differences in race and sex,people’s body shapes vary.According to European guidelines,the patch should measure 10 cm×15 cm.If any part of the MPO is dissected,injury to the nerves,vascular network,or organs may occur during surgery,thereby leading to inguinal discomfort,pain,and seroma formation after surgery.Therefore,accurate localization and measurement of the boundary of the MPO are crucial for selecting the optimal patch for inguinal hernia repair.AIM To compare the size of the MPO measured on three-dimensional multislice spiral computed tomography(CT)with that measured via laparoscopy and explore the relevant factors influencing the size of the MPO.METHODS Clinical data from 74 patients who underwent laparoscopic tension-free inguinal hernia repair at the General Surgery Department of the First Affiliated Hospital of Anhui University of Science and Technology between September 2022 and July 2024 were collected and analyzed retrospectively.Transabdominal preperitoneal was performed.Sixty-four males and 10 females,with an average age of 58.30±12.32 years,were included.The clinical data of the patients were collected.The boundary of the MPO was measured on three-dimensional CT images before surgery and then again during transabdominal preperitoneal.All the preoperative and intraoperative data were analyzed via paired t-tests.A t-test was used for comparisons of age,body mass index,and sex between the groups.In the comparative analysis,a P value less than 0.05 indicated a significant difference.RESULTS The boundaries of the MPO on 3-dimensional CT images measured 7.05±0.47 cm and 6.27±0.61 cm,and the area of the MPO was 19.54±3.33 cm^(2).The boundaries of the MPO during surgery were 7.18±0.51 cm and 6.17±0.40 cm.The errors were not statistically significant.However,the intraoperative BD(the width of the MPO,P=0.024,P<0.05)and preoperative AC(the length of the MPO,P=0.045,P<0.05)significantly differed according to sex.The AC and BD measurements before and during surgery were not significantly different according to age,body mass index,hernia side or hernia type(P>0.05).CONCLUSION The application of this technology can aid in determining the most appropriate dissection range and patch size. 展开更多
关键词 HERNIA INGUINAL Myopectineal orifice three-dimensional reconstruction Computed tomography Inguinal hernia
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A New Three-Dimensional Voronoi Cell Finite Element Method for Particle-Reinforced Composites
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作者 Huici Dong Ran Guo 《Acta Mechanica Solida Sinica》 2026年第1期90-100,共11页
This paper proposes a state-of-the-art three-dimensional Voronoi cell finite element method(3D VCFEM)aimed at investigating the mechanical properties of particle-reinforced composites(PRCs)in space under different mic... This paper proposes a state-of-the-art three-dimensional Voronoi cell finite element method(3D VCFEM)aimed at investigating the mechanical properties of particle-reinforced composites(PRCs)in space under different microstructural properties.Firstly,the modified residual energy generalized function of 3D VCFEM was proposed by applying the hybrid stress element method,and the element format of the 3D Voronoi element was constructed.On this basis,the interaction between the matrix and the inclusions was considered,and the higher-order stress function including the interaction stress term was constructed.Secondly,to solve the difficulty of integrating easily due to the complexity and irregularity of the integration region in space,Delaunay tetrahedra were introduced within the 3D Voronoi element for mesh refinement.It simplified the integration process.Finally,to verify the accuracy and efficiency of the 3D VCFEM model,comparative models of 3D VCFENM and FEM were established for analysis and discussion.The stress field and strain field were compared and analyzed for the first time.An example was also given for the presence of a large number of randomly distributed inclusion particles.The results showed that under the same accuracy,3D VCFEM had the advantages of convenient mesh delineation and high computational efficiency compared with FEM,which provided a new way of thinking to analyze the actual PCRs. 展开更多
关键词 three-dimensional Voronoi cell finite element method Particle-reinforced composites Integral domain refinement Hybrid stress element method
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Artificial intelligence-aided semi-automatic joint trace detection from textured three-dimensional models of rock mass 被引量:1
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作者 Seyedahmad Mehrishal Jineon Kim +1 位作者 Yulong Shao Jae Joon Song 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期1973-1985,共13页
It is of great importance to obtain precise trace data,as traces are frequently the sole visible and measurable parameter in most outcrops.The manual recognition and detection of traces on high-resolution three-dimens... It is of great importance to obtain precise trace data,as traces are frequently the sole visible and measurable parameter in most outcrops.The manual recognition and detection of traces on high-resolution three-dimensional(3D)models are relatively straightforward but time-consuming.One potential solution to enhance this process is to use machine learning algorithms to detect the 3D traces.In this study,a unique pixel-wise texture mapper algorithm generates a dense point cloud representation of an outcrop with the precise resolution of the original textured 3D model.A virtual digital image rendering was then employed to capture virtual images of selected regions.This technique helps to overcome limitations caused by the surface morphology of the rock mass,such as restricted access,lighting conditions,and shading effects.After AI-powered trace detection on two-dimensional(2D)images,a 3D data structuring technique was applied to the selected trace pixels.In the 3D data structuring,the trace data were structured through 2D thinning,3D reprojection,clustering,segmentation,and segment linking.Finally,the linked segments were exported as 3D polylines,with each polyline in the output corresponding to a trace.The efficacy of the proposed method was assessed using a 3D model of a real-world case study,which was used to compare the results of artificial intelligence(AI)-aided and human intelligence trace detection.Rosette diagrams,which visualize the distribution of trace orientations,confirmed the high similarity between the automatically and manually generated trace maps.In conclusion,the proposed semi-automatic method was easy to use,fast,and accurate in detecting the dominant jointing system of the rock mass. 展开更多
关键词 Automatic trace detection Digital joint mapping Rock discontinuities characterization three-dimensional(3D)trace network
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Dynamic modeling of a three-dimensional braided composite thin plate considering braiding directions 被引量:1
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作者 Chentong GAO Huiyu SUN +1 位作者 Jianping GU W.M.HUANG 《Applied Mathematics and Mechanics(English Edition)》 2025年第1期123-138,共16页
Currently,there are a limited number of dynamic models available for braided composite plates with large overall motions,despite the incorporation of three-dimensional(3D)braided composites into rotating blade compone... Currently,there are a limited number of dynamic models available for braided composite plates with large overall motions,despite the incorporation of three-dimensional(3D)braided composites into rotating blade components.In this paper,a dynamic model of 3D 4-directional braided composite thin plates considering braiding directions is established.Based on Kirchhoff's plate assumptions,the displacement variables of the plate are expressed.By incorporating the braiding directions into the constitutive equation of the braided composites,the dynamic model of the plate considering braiding directions is obtained.The effects of the speeds,braiding directions,and braided angles on the responses of the plate with fixed-axis rotation and translational motion,respectively,are investigated.This paper presents a dynamic theory for calculating the deformation of 3D braided composite structures undergoing both translational and rotational motions.It also provides a simulation method for investigating the dynamic behavior of non-isotropic material plates in various applications. 展开更多
关键词 three-dimensional(3D)braided composite braiding direction composite thin plate large overall motion dynamic model
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Investigation into the degradation of 2,4,6-trichlorophenol utilizing a three-dimensional electrocatalytic reactor filled with fluorine-doped copper-carbon particle electrodes
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作者 Hongrui Zhang Wenyu Huang +4 位作者 Hainong Song Hanhui Yan Jia Zhang Fang Zhong Huilan Li 《Journal of Environmental Sciences》 2025年第9期701-719,共19页
The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated cata... The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated catalytic activity and minimal energy consumption continues to pose a significant challenge.In this research,Fluorine-doped copper-carbon(F/Cu-GAC)particle electrodes were effectively synthesized through an impregnationcalcination technique,utilizing granular activated carbon as the carrier and fluorinedoped modified copper oxides as the catalytic agents.The particle electrodes were subsequently utilized to promote the degradation of 2,4,6-trichlorophenol(2,4,6-TCP)in a threedimensional electrocatalytic reactor(3DER).The F/Cu-GAC particle electrodes were polarized under the action of electric field,which promoted the heterogeneous Fenton-like reaction in which H2O2 generated by two-electron oxygen reduction reaction(2e-ORR)of O_(2) was catalytically decomposed to·OH.The 3DER equipped with F/Cu-GAC particle electrodes showed 100%removal of 2,4,6-TCP and 79.24%removal of TOC with a specific energy consumption(EC)of approximately 0.019 kWh/g·COD after 2 h of operation.The F/Cu-GAC particle electrodes exhibited an overpotential of 0.38 V and an electrochemically active surface area(ECSA)of 715 cm^(2),as determined through linear sweep voltammetry(LSV)and cyclic voltammetry(CV)assessments.These findings suggest a high level of electrocatalytic performance.Furthermore,the catalytic mechanism of the 3DER equipped with F/Cu-GAC particle electrodes was elucidated through the application of X-ray photoelectron spectroscopy(XPS),electron spin resonance(ESR),and active species capture experiments.This investigation offers a novel approach for the effective degradation of 2,4,6-TCP. 展开更多
关键词 2 4 6-TRICHLOROPHENOL Heterogeneous Fenton-like process three-dimensional electrocatalytic reactor three-dimensional particle electrode system Fluorine-doped copper-carbon particle electrodes
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Resection of a ganglioneuroma encasing major blood vessels using three-dimensional laparoscopy combined with organ suspension:A case report
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作者 Guo-Zhen Wu Shen-Zhe Fang +1 位作者 Shi-An Yu Min Yu 《World Journal of Gastrointestinal Surgery》 2025年第8期467-475,共9页
BACKGROUND Ganglioneuroma is a rare,well-differentiated,slow-growing benign tumor of the peripheral nerves,with surgical resection being the only curative treatment.Surgical resection of ganglioneuromas encasing major... BACKGROUND Ganglioneuroma is a rare,well-differentiated,slow-growing benign tumor of the peripheral nerves,with surgical resection being the only curative treatment.Surgical resection of ganglioneuromas encasing major blood vessels remains a substantial clinical challenge.Traditionally,these cases often require open abdominal surgery or combined organ resections,and in some instances,the tumors are considered unresectable.Currently,no reports have described the resection of such tumors via laparoscopy.CASE SUMMARY A 35-year-old woman was admitted to our hospital after the incidental discovery of a retroperitoneal space-occupying lesion.Imaging revealed a mass with the celiac axis and superior mesenteric artery passing through it.A neurogenic tumor was suspected,with ganglioneuroma being the most likely diagnosis.Following comprehensive preoperative preparation,the retroperitoneal tumor was resected using a three-dimensional laparoscopy combined with an organ suspension technique.The surgical approach involved incising the tumor along the vascular axis and conducting meticulous,vascular-preserving tumor excision.The operation lasted approximately 458 minutes,with an estimated blood loss of 50 mL.The patient was discharged on the 8th postoperative day.A transient liver injury occurred after surgery but improved rapidly.After 11 months of postoperative follow-up,no complications or tumor recurrence were observed.CONCLUSION This case illustrates the feasibility of minimally invasive laparoscopic resection for retroperitoneal ganglioneuromas encasing major blood vessels. 展开更多
关键词 Ganglioneuromas Retroperitoneal three-dimensional laparoscopy Organ suspension Case report
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Three-dimensional spectral analysis of gravity waves from airglow observations over Northwest China
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作者 QinZeng Li JiYao Xu +3 位作者 Wei Yuan Xiao Liu YaJun Zhu WeiJun Liu 《Earth and Planetary Physics》 2025年第4期988-994,共7页
The three-dimensional spectral analysis method was applied to airglow data from September 2023 to August 2024 derivedfrom an OH airglow imager located at the Hejing station (42.79°N, 83.73°E) to study the pr... The three-dimensional spectral analysis method was applied to airglow data from September 2023 to August 2024 derivedfrom an OH airglow imager located at the Hejing station (42.79°N, 83.73°E) to study the propagation characteristics of gravity waves(GWs) over Northwest China. We found that obvious seasonal variations occur in the propagation of GWs. In spring, GWs mainlypropagate in the northeast direction. In summer and autumn, GWs mainly propagate in the north direction. However, GWs mainlypropagate in the south direction in winter. The direction of GW propagation in the zonal direction is controlled by the wind-filteringeffect, whereas the north–south meridional direction is mainly determined by the location of the wave source. We found that the averageenergy spectrum exhibits a 10%–20% higher intensity in summer and winter compared with spring and autumn. For the first time, wereport the seasonal variation characteristics of GWs over the inland areas of Northwest China, which is of great significance forunderstanding the regional distribution characteristics of GWs. 展开更多
关键词 AIRGLOW gravity wave three-dimensional spectral analysis seasonal variation
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Effects of macrophages on the osteogenic differentiation of adipose tissue-derived stem cells in two-dimensional and three-dimensional cocultures
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作者 He-Ao Zhang Bo-Yu Zhang Hong-Bo Tang 《World Journal of Stem Cells》 2025年第2期84-95,共12页
BACKGROUND Fracture is one of the most pervasive injuries in the musculoskeletal system,and there is a complex interaction between macrophages and adipose tissue-derived stem cells(ADSCs)in fracture healing.However,tw... BACKGROUND Fracture is one of the most pervasive injuries in the musculoskeletal system,and there is a complex interaction between macrophages and adipose tissue-derived stem cells(ADSCs)in fracture healing.However,two-dimensional(2D)coculture of macrophages and ADSCs can not accurately mimic the in vivo cell microenvironment.AIM To establish both 2D and 3D osteogenic coculture models to investigate the interaction between macrophages and ADSCs.METHODS After obtaining ADSCs from surgery and inducing differentiation of the THP1 cell line,we established 2D and 3D osteogenic coculture models.To assess the level of osteogenic differentiation,we used alizarin red staining and measured the relative expression levels of osteogenic differentiation markers osteocalcin,Runt-related transcription factor 2,and alkaline phosphatase through polymerase chain reaction.Verification was conducted by analyzing the expression changes of N-cadherin and the activation of the Wnt/β-catenin signaling pathway using western blotting.RESULTS In this study,it was discovered that macrophages in 3D culture inhibited osteogenic differentiation of ADSCs,contrary to the effect in 2D culture.This observation confirmed the significance of intricate intercellular connections in the 3D culture environment.Additionally,the 3D culture group exhibited significantly higher N-cadherin expression and showed reducedβ-catenin and Wnt1 protein levels compared to the 2D culture group.CONCLUSION Macrophages promoted ADSC osteogenic differentiation in 2D culture conditions but inhibited it in 3D culture.The 3D culture environment might inhibit the Wnt/β-catenin signaling pathway by upregulating N-cadherin expression,ultimately hindering the osteogenic differentiation of ADSCs.By investigating the process of osteogenesis in ADSCs,this study provides novel ideas for exploring 3D osteogenesis in ADSCs,fracture repair,and other bone trauma repair. 展开更多
关键词 FRACTURE Adipose tissue-derived stem cells Osteogenic differentiation three-dimensional cell culture N-CADHERIN
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Superior decomposition of xenobiotic RB5 dye using three-dimensional electrochemical treatment:Response surface methodology modelling,artificial intelligence,and machine learning-based optimisation approaches
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作者 Voravich Ganthavee Antoine P.Trzcinski 《Water Science and Engineering》 2025年第1期1-10,共10页
The highly efficient electrochemical treatment technology for dye-polluted wastewater is one of hot research topics in industrial wastewater treatment.This study reported a three-dimensional electrochemical treatment ... The highly efficient electrochemical treatment technology for dye-polluted wastewater is one of hot research topics in industrial wastewater treatment.This study reported a three-dimensional electrochemical treatment process integrating graphite intercalation compound(GIC)adsorption,direct anodic oxidation,and·OH oxidation for decolourising Reactive Black 5(RB5)from aqueous solutions.The electrochemical process was optimised using the novel progressive central composite design-response surface methodology(CCD-NPRSM),hybrid artificial neural network-extreme gradient boosting(hybrid ANN-XGBoost),and classification and regression trees(CART).CCD-NPRSM and hybrid ANN-XGBoost were employed to minimise errors in evaluating the electrochemical process involving three manipulated operational parameters:current density,electrolysis(treatment)time,and initial dye concentration.The optimised decolourisation efficiencies were 99.30%,96.63%,and 99.14%for CCD-NPRSM,hybrid ANN-XGBoost,and CART,respectively,compared to the 98.46%RB5 removal rate observed experimentally under optimum conditions:approximately 20 mA/cm^(2) of current density,20 min of electrolysis time,and 65 mg/L of RB5.The optimised mineralisation efficiencies ranged between 89%and 92%for different models based on total organic carbon(TOC).Experimental studies confirmed that the predictive efficiency of optimised models ranked in the descending order of hybrid ANN-XGBoost,CCD-NPRSM,and CART.Model validation using analysis of variance(ANOVA)revealed that hybrid ANN-XGBoost had a mean squared error(MSE)and a coefficient of determination(R^(2))of approximately 0.014 and 0.998,respectively,for the RB5 removal efficiency,outperforming CCD-NPRSM with MSE and R^(2) of 0.518 and 0.998,respectively.Overall,the hybrid ANN-XGBoost approach is the most feasible technique for assessing the electrochemical treatment efficiency in RB5 dye wastewater decolourisation. 展开更多
关键词 three-dimensional electrochemical treatment Dye-polluted wastewater Artificial intelligence Machine learning Optimisation Analysis of variance Error function analysis
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The detection of keratoconus using a three-dimensional corneal model derived from anterior segment optical coherence tomography
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作者 Sang Ngoc Tran Isa S.K.Mohammed +1 位作者 Zeshan Tariq Wuqaas M.Munir 《Annals of Eye Science》 2025年第3期73-82,共10页
Background:Traditional imaging approaches to keratoconus(KCN)have thus far failed to produce a standardized approach for diagnosis.While many diagnostic modalities and metrics exist,none have proven robust enough to b... Background:Traditional imaging approaches to keratoconus(KCN)have thus far failed to produce a standardized approach for diagnosis.While many diagnostic modalities and metrics exist,none have proven robust enough to be considered a gold standard.This study aims to introduce novel metrics to differentiate between KCN and healthy corneas using three-dimensional(3D)measurements of surface area and volume.Methods:This retrospective observational study examined KCN patients along with healthy control patients between the ages of 20 and 79 years old at the University of Maryland,Baltimore.The selected patients underwent a nine-line raster scan anterior segment optical coherence tomography(AS-OCT).ImageJ was used to determine the central 6 mm of each image and each corneal image was then divided into six 1 mm segments.Free-D software was then used to render the nine different images into a 3D model to calculate corneal surface area and volume.A two-tailed Mann-Whitney test was used to assess statistical significance when comparing these subsets.Results:Thirty-three eyes with KCN,along with 33 healthy control,were enrolled.There were statistically significant differences between the healthy and KCN groups in the metric of anterior corneal surface area(13.927 vs.13.991 mm^(2),P=0.046),posterior corneal surface area(14.045 vs.14.173 mm^(2),P<0.001),and volume(8.430 vs.7.773 mm3,P<0.001)within the central 6 mm.Conclusions:3D corneal models derived from AS-OCT can be used to measure anterior corneal surface area,posterior corneal surface area,and corneal volume.All three parameters are statistically different between corneas with KCN and healthy corneas.Further study and application of these parameters may yield new methodologies for the detection of KCN. 展开更多
关键词 CORNEA ectASIA keratoconus(KCN) anterior segment optical coherence tomography(AS-OCT) three-dimensional model(3D model)
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Three-Dimensional Prospectivity Modeling of Jinshan Ag-Au Deposit,Southern China by Weights-of-Evidence
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作者 Fan Xiao Qiuming Cheng +1 位作者 Weisheng Hou Frederik P.Agterberg 《Journal of Earth Science》 2025年第5期2038-2057,共20页
To comprehensively utilize the valuable geological map,exploration profile,borehole,and geochemical logging data and the knowledge on the formation of the Jinshan Ag-Au deposit for forecasting the exploration targets ... To comprehensively utilize the valuable geological map,exploration profile,borehole,and geochemical logging data and the knowledge on the formation of the Jinshan Ag-Au deposit for forecasting the exploration targets of concealed ore bodies,three-dimensional Mineral Prospectivity Modeling(MPM)of the deposit has been conducted using the weights-of-evidence(WofE)method.Conditional independence between evidence layers was tested,and the outline results using the prediction-volume(P-V)and Student's t-statistic methods for delineating favorable mineralization areas from continuous posterior probability map were critically compared.Four exploration targets delineated ultimately by the Student's t-statistic method for the discovery of minable ore bodies in each of the target areas were discussed in detail.The main conclusions include:(1)three-dimensional modeling of a deposit using multi-source reconnaissance data is useful for MPM in interpreting their relationships with known ore bodies;(2)WofE modeling can be used as a straightforward tool for integrating deposit model and reconnaissance data in MPM;(3)the Student's t-statistic method is more applicable in binarizing the continuous prospectivity map for exploration targeting than the PV approach;and(4)two target areas within high potential to find undiscovered ore bodies were diagnosed to guide future near-mine exploration activities of the Jinshan deposit. 展开更多
关键词 three-dimensional modeling mineral prospectivity mapping exploration targeting WEIGHTS-OF-EVIDENCE C-V fractal model Jinshan Ag-Au deposit mineral deposits economic geology
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Assessment of Gastric Cancer: Value of Two-phase Multidetector-row Spiral CT Three-dimensional Reconstruction Technique 被引量:4
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作者 李震 胡道予 +2 位作者 肖明 张进华 宋金梅 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第6期365-368,共4页
Abstract Objective: To evaluate the diagnostic value of two-phase multidetector-row spiral CT threedimensional reconstruction technique in TNM staging of gastric cancer. Methods: In 29 patients with gastric carcinom... Abstract Objective: To evaluate the diagnostic value of two-phase multidetector-row spiral CT threedimensional reconstruction technique in TNM staging of gastric cancer. Methods: In 29 patients with gastric carcinoma pathologically conformed, plan scans were done firstly. Two-phase spiral CT was performed within one breathhold each. Distension of the stomach was achieved by intravenous application of anisodamine and effervescent granules. After bolus injection of contrast medium, scanning was performed in the arterial and venous phase, and the source images were thin reconstructed. The stomach to three-dimension analysis was constructed by volume rendering (VR) multiplanaz volume reconstruction (MPVR), shaded surface display (SSD) and CT virtual gastroscopy (CTVG) technique. In combination with the sources images, gastric tumour invasion and lymph node metastasis was assessed, and TNM staging was performed. Results: In 29 cases of gastric carcinoma, the sensitivity and specificity of two-phase multidetector-row spiral CT three-dimensional reconstruction technique in T1, T2, T3 and Ta staging, the sensitivity and specificity was 50% and 50%, 87.5% and 77.8%, 83.3% and 76.9% and 100% and 80% respectively. For the N staging, the sensitivity and specificity in No, N1, and N2 N3 was 83.3% and 71.4%, 87.5% and 77.8% and 81.8% and 75% respectively. The sensitivity and the specificity for M1 staging was 100%. Conclusion: The reconstruction technique in combination with 16-slices spiral-CT can perform TNM staging well and effectively guide the choice of the surgical procedures for gastric cancer. 展开更多
关键词 SPIRAL-CT gastric carcinoma three-dimensional reconstruction
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Three-dimensional arbitrarily anisotropic modeling for time-domain airborne electromagnetic surveys 被引量:3
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作者 黄威 贲放 +5 位作者 殷长春 孟庆敏 李文杰 廖桂香 吴珊 西永在 《Applied Geophysics》 SCIE CSCD 2017年第3期431-440,462,共11页
Electrically anisotropic strata are abundant in nature, so their study can help our data interpretation and our understanding of the processes of geodynamics. However, current data processing generally assumes isotrop... Electrically anisotropic strata are abundant in nature, so their study can help our data interpretation and our understanding of the processes of geodynamics. However, current data processing generally assumes isotropic conditions when surveying anisotropic structures, which may cause discrepancies between reality and electromagnetic data interpretation. Moreover, the anisotropic interpretation of the time-domain airborne electromagnetic (TDAEM) method is still confined to one dimensional (1D) cases, and the corresponding three-dimensional (3D) numerical simulations are still in development. In this study, we expanded the 3D TDAEM modeling of arbitrarily anisotropic media. First, through coordinate rotation of isotropic conductivity, we obtained the conductivity tensor of an arbitrary anisotropic rock. Next, we incorporated this into Maxwell's equations, using a regular hexahedral grid of vector finite elements to subdivide the solution area. A direct solver software package provided the solution for the sparse linear equations that resulted. Analytical solutions were used to verify the accuracy and feasibility of the algorithm. The proven model was then applied to analyze the effects of arbitrary anisotropy in 3D TDAEM via the distribution of responses and amplitude changes, which revealed that different anisotropy situations strongly affected the responses of TDAEM. 展开更多
关键词 three-dimensional time-domain airborne electromagnetic arbitrary anisotropy vector finite element
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Three-dimensional morphometric analysis for hepatectomy of centrally located hepatocellular carcinoma:A pilot study 被引量:24
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作者 Fei Tian Jian-Xiong Wu +8 位作者 Wei-Qi Rong Li-Ming Wang Fan Wu Wei-Bo Yu Song-Lin An Fa-Qiang Liu Li Feng Chao Bi Yun-He Liu 《World Journal of Gastroenterology》 SCIE CAS 2015年第15期4607-4619,共13页
AIM: To describe a three-dimensional model(3DM) to accurately reconstruct anatomic relationships of centrally located hepatocellular carcinomas(HCCs).METHODS: From March 2013 to July 2014, reconstructions and visual s... AIM: To describe a three-dimensional model(3DM) to accurately reconstruct anatomic relationships of centrally located hepatocellular carcinomas(HCCs).METHODS: From March 2013 to July 2014, reconstructions and visual simulations of centrally located HCCs were performed in 39 patients using a 3D subject-based computed tomography(CT) model with customdeveloped software. CT images were used for the 3D reconstruction of Couinaud's pedicles and hepatic veins, and the calculation of corresponding tumor territories and hepatic segments was performed using Yorktal DMIT software. The respective volume, surgical margin, and simulated virtual resection of tumors were also estimated by this model preoperatively. All patients were treated surgically and the results were retrospectively assessed. Clinical characteristics, imaging data, procedure variables, pathologic features, and postoperative data were recorded and compared to determine the reliability of the model.RESULTS: 3D reconstruction allowed stereoscopic identification of the spatial relationships between physiologic and pathologic structures, and offered quantifiable liver resection proposals based on individualized liver anatomy. The predicted values were consistent with the actual values for tumor mass volume(82.4 ± 109.1 m L vs 84.1 ± 108.9 m L, P = 0.910), surgical margin(10.1 ± 6.2 mm vs 9.1 ± 5.9 mm, P = 0.488), and maximum tumor diameter(4.61 ± 2.16 cm vs 4.53 ± 2.14 cm, P = 0.871). In addition,the number and extent of portal venous ramifications, as well as their relation to hepatic veins, were visualized. Preoperative planning based on simulated resection facilitated complete resection of large tumors located in the confluence of major vessels. And most of the predicted data were correlated with intraoperative findings.CONCLUSION: This 3DM provides quantitative morphometry of tumor masses and a stereo-relationship with adjacent structures, thus providing a promising technique for the management of centrally located HCCs. 展开更多
关键词 Centrally located HEPATectOMY Hepatocellularcarcinoma LIVER three-dimensional MODEL
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Differentiation of focal liver lesions using three-dimensional ultrasonography: Retrospective and prospective studies 被引量:12
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作者 Kazushi Numata Manabu Morimoto +4 位作者 Akito Nozaki Michio Ueda Masaaki Kondo Satoshi Morita Katsuaki Tanaka 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第17期2109-2119,共11页
AIM: To differentiate focal liver lesions based on enhancement patterns using three-dimensional ultrasonography (3D US) with perflubutane-based contrast agent.METHODS: Two hundred and eighty two patients with focal li... AIM: To differentiate focal liver lesions based on enhancement patterns using three-dimensional ultrasonography (3D US) with perflubutane-based contrast agent.METHODS: Two hundred and eighty two patients with focal liver lesions,including 168 hepatocellular carcinomas (HCCs),63 metastases,40 hemangiomas and 11 focal nodular hyperplasias (FNHs),were examined by 3D US with perflubutane-based contrast agent.Tomographic ultrasound images and sonographic angiograms were reconstructed.Among 282 lesions,enhancement patterns of 163 lesions between January 2007 and October 2007 were analyzed retrospectively.Then from November 2007 to May 2008,compared with contrast-enhanced (CE) 2D US,CE 3D US was performed on 119 lesions for prospective differential diagnosis.Sensitivity,specificity,area under receiver operating characteristic curve (Az) and inter-reader agreement were assessed.RESULTS: With the tridimensional view,dominant enhancement patterns were revealed as diffuse enhancement or peripheral ring-like enhancement,followed with washout change for HCCs or metastases,respectively,and peripheral nodular enhancement or diffuse enhancement with spoke-wheel arteries,followed by persistent enhancement for hemangiomas or FNHs,respectively.At CE 3D US,the prospective differentiation of lesions showed sensitivity 92% (mean for two readers),specificity 91% and Az value 0.95 for HCCs,84%,97%,and 0.95 for metastases,91%,98%,and 0.98 for hemangiomas and 80%,99%,and 0.99 for FNHs,respectively,while good to excellent inter-reader agreement was achieved.No significant difference exists between prospective diagnosis accuracy at CE 3D US and that at CE 2D US.CONCLUSION: CE 3D US provides a spatial perspective for liver tumor enhancement,and could help in differentiating focal liver lesions. 展开更多
关键词 three-dimensional ULTRASONOGRAPHY Contrast agent LIVER NEOPLASMS
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Three-dimensional vs two-dimensional video assisted thoracoscopic esophagectomy for patients with esophageal cancer 被引量:6
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作者 Zhao Li Jing-Pei Li +6 位作者 Xiong Qin Bin-Bin Xu Yu-Dong Han Si-Da Liu Wen-Zhuo Zhu Ming-Zheng Peng Qiang Lin 《World Journal of Gastroenterology》 SCIE CAS 2015年第37期10675-10682,共8页
AIM: To define the benefits of three-dimensional video-assisted thoracoscopic esophagectomy(3D-VATE)over 2D-VATE for esophageal cancer.METHODS: A total of 93 patients with esophageal cancer including 45 patients recei... AIM: To define the benefits of three-dimensional video-assisted thoracoscopic esophagectomy(3D-VATE)over 2D-VATE for esophageal cancer.METHODS: A total of 93 patients with esophageal cancer including 45 patients receiving 3D-VATE and48 receiving 2D-VATE were evaluated. Data related to patient and cancer characteristics, operating time,intraoperative bleeding, morbidity and mortality,postoperative inflammatory markers, Numerical Rating Scale for postoperative pain, Constant-Murley rating system for shoulder recovery and oxygenation index(OI) were collected. All medical records were retrieved from a prospectively maintained oncological database at our institution. A retrospective study was performed to compare the short-term surgical outcomes between the two groups.RESULTS: No significant differences were found between the two groups in either morbidity or mortality(P = 0.328). An enhanced surgical recovery was noted in the 3D group as indicated by shortened thoracoscopic operation time(3D vs 2D: 68 ± 13.79 min vs 83 ± 13min, P < 0.01), minor intraoperative blood loss(3D vs 2D: 68.2 ± 10.7 ml vs 89.8 ± 10.4 ml, P < 0.01),earlier chest tube removal(3D vs 2D: 2.67 ± 1.01 vs3.75 ± 1.15 d, P < 0.01), shorter length of hospital stay(3D vs 2D: 9.07 ± 2.00 vs 10.85 ± 3.40 d, P <0.01), lower in-hospital expenses(3D vs 2D: 74968.4± 9637.8 vs 86211.1 ± 8519.7 RMB, P < 0.01), lower pain intensity(P < 0.01) and faster recovery of the left shoulder function(P < 0.01). Better preservation of the pulmonary function was also found in the 3D group as the decline of the OI post operation was significantly lower than that of the 2D group(P < 0.01). Changes of postoperative inflammatory markers, including procalcitonin [postoperative days(PODs) 4 and 7: P <0.01], peripheral granulocytes(PODs 1, 4 and 7: P <0.01) and hypersensitive C-reactive protein(POD 4: P< 0.01) in 3D-VATE patients were less than those in the 2D group. Moreover, utilization of the 3D technique extended the dissection of the thoracic lymph nodes(P < 0.01), with better exposure of nodes in the left recurrent laryngeal nerve(P = 0.031).CONCLUSION: 3D-VATE could be a more viable technique over 2D-VATE in terms of short-term outcomes for patients with esophageal cancer. 展开更多
关键词 ESOPHAGEAL cancer three-dimensional videoassisted
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Construction of three-dimensional hierarchical porous nitrogen-doped re duce d graphene oxide/hollow cobalt ferrite composite aerogels toward highly efficient electromagnetic wave absorption 被引量:15
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作者 Jing Xu Ruiwen Shu +1 位作者 Zongli Wan Jianjun Shi 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第1期193-200,共8页
The development of graphene-based composites with low density,robust absorption,wide bandwidth and thin thickness remained a great challenge in the field of electromagnetic(EM)absorption.In this work,nitrogen-doped re... The development of graphene-based composites with low density,robust absorption,wide bandwidth and thin thickness remained a great challenge in the field of electromagnetic(EM)absorption.In this work,nitrogen-doped reduced graphene oxide/hollow cobalt ferrite(NRGO/hollow CoFe_(2)O_(4))composite aerogels were constructed by a solvothermal and hydrothermal two-step route.Results demonstrated that the as-fabricated composite aerogels had the ultralow density and a unique three-dimensional(3D)network structure,and lots of hollow CoFe_(2)O_(4)microspheres were almost homogeneously distributed on the wrinkled surfaces of lamellar NRGO.Moreover,superior EM absorbing capacity could be achieved by modulating the ferrite structure,addition amounts of hollow CoFe_(2)O_(4)and thicknesses.It was noteworthy that the NRGO/hollow CoFe_(2)O_(4)composite aerogel with the addition amount of ferrite of 15.0 mg pos-sessed the minimum reflection loss of-44.7 dB and maximum absorption bandwidth of 5.2 GHz(from 12.6 to 17.8 GHz)at a very thin thickness of 1.8 mm and filling ratio of 15.0 wt.%.Furthermore,the possible EM attenuation mechanism had been proposed.The results of this work would be helpful for developing RGO-based 3D composites as lightweight,thin and highly efficient EM wave absorbers. 展开更多
关键词 Graphene Composite aerogels Hollow ferrite three-dimensional network Nitrogen doping
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