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《海军军医大学学报》 北大核心 2026年第4期F0004-F0004,共1页
医学文摘(EMBASE,荷兰)斯高帕斯(Scopus,荷兰)化学文摘(CA,美国)剑桥科学文摘(Cambridge Scientific Abstracts,美国)国际农业与生物科学研究中心文摘(CAB Abstracts,英国)公共健康研究数据库(Global Health,英国)。
关键词 indexED ABSTRACTED 化学文摘 Cambridge Scientific Abstracts SCOPUS EMBASE
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Sharp Bounds for ABS Index of Line,Total and Mycielski Graphs
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作者 YE Qingfang LI Fengwei 《数学进展》 北大核心 2026年第1期45-59,共15页
The atom-bond sum-connectivity(ABS)index,put forward by[J.Math.Chem.,2022,60(10):20812093],exhibits a strong link with the acentric factor of octane isomers.The experimental physico-chemical properties of octane isome... The atom-bond sum-connectivity(ABS)index,put forward by[J.Math.Chem.,2022,60(10):20812093],exhibits a strong link with the acentric factor of octane isomers.The experimental physico-chemical properties of octane isomers,such as boiling point,of formation are found to be better measured by the ABS index than by the Randi,atom-bond connectivity(ABC),and sum-connectivity(SC)indices.One important source of information for researching the molecular structure is the bounds for its topological indices.The extrema of the ABS index of the line,total,and Mycielski graphs are calculated in this work.Moreover,the pertinent extremal graphs were illustrated. 展开更多
关键词 ABS index line graph total graph Mycielski graph
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Vulnerability assessment in fractured aquifer using improved vulnerability index:Applied to Gabes aquifer,Southeastern Tunisia
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作者 Mounir Atoui Belgacem Agoubi 《Journal of Groundwater Science and Engineering》 2026年第1期69-82,共14页
The Gabes aquifer system,located in southeastern Tunisia,is a crucial resource for supporting local socio-economic activities.Due to its dual porosity structure,is particularly vulnerable to pollution.This study aims ... The Gabes aquifer system,located in southeastern Tunisia,is a crucial resource for supporting local socio-economic activities.Due to its dual porosity structure,is particularly vulnerable to pollution.This study aims to develop a hybrid model that combines the Fracture Aquifer Index(FAI)with the conventional GOD(Groundwater occurrence,Overall lithology,Depth to water table)method,to assess groundwater vulnerability in fractured aquifer.To develop the hybrid model,the classical GOD method was integrated with FAI to produce a single composite index.Each parameter within both GOD and FAI was scored,and a final index was calculated to delineate vulnerable areas.The results show that the study area can be classified into four vulnerability levels:Very low,low,moderate,and high,indicating that approximately 8%of the area exhibits very low vulnerability,29%has low vulnerability,25%falls into the moderate category,and 38%is considered highly vulnerable.The FAI-GOD model further incorporates fracture network characteristics.This refinement reduces the classification to three vulnerability classes:Low,medium,and high.The outcomes demonstrate that 46%of the area is highly vulnerable due to a dense concentration of fractures,while 17%represents an intermediate zone characterized by either shallow or deeper fractures.In contrast,37%corresponds to areas with lightly fractured rock,where the impact on vulnerability is minimal.Multivariate statistical analysis was employed using Principal Components Analysis(PCA)and Hierarchical Cluster Analysis(HCA)on 24 samples across six variables.The first three components account for over 76%of the total variance,reinforcing the significance of fracture dynamics in classifying vulnerability levels.The FAI-GOD model removes the very-low-vulnerability class and expands the spatial extent of low-and high-vulnerability zones,reflecting the dominant influence of fracture networks on aquifer sensitivity.While both indices use a five-class system,FAI-GOD redistributes vulnerability by eliminating very-low-vulnerability areas and amplifying low/high categories,highlighting the critical role of fractures.A strong correlation(R2=0.94)between the GOD and FAI-GOD indices,demonstrated through second-order polynomial regression,confirms the robustness of the FAI-GOD model in accurately predicting vulnerability to pollution.This model provides a useful framework for assessing the vulnerability of complex aquifers and serves as a decision-making tool for groundwater managers in similar areas. 展开更多
关键词 GROUNDWATER Aquifer vulnerability Fractured media FAI-GOD index GOD index GIS
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Spatial morphology optimization for reconciling urban expansion with ecological integrity based on a multi-level ecological network framework
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作者 LU Jie JIAO Sheng CHEN Xingli 《Journal of Geographical Sciences》 2026年第2期399-420,共22页
Urban spatial morphology(USM)optimization is critical to balancing biodiversity conservation and sustainable urbanization.However,previous studies predominantly focused on the socio-economic efficiency and static ecol... Urban spatial morphology(USM)optimization is critical to balancing biodiversity conservation and sustainable urbanization.However,previous studies predominantly focused on the socio-economic efficiency and static ecological metrics and rarely addressed the dynamic USM optimization across spatial scales.Here,we developed a multi-level ecological network(MEN)framework to resolve the tension between urban expansion and ecological integrity.By integrating the cost-weighted distance analysis with a hierarchical network transmission mechanism,we established a cross-scale spatial optimization system,which coordinated the regional ecological corridors and local habitat patches.Comparative experiments with conventional single-scale approaches and scenario simulations using the PLUS model show that the MEN framework had superior performance in three dimensions:(1)spatial governance:the primary-level network(peri-urban natural reserves)effectively contained urban sprawl,and the secondary-level network(intra-urban green corridors)mitigated habitat fragmentation and improved the built-environment;(2)scenario robustness:the model maintained an optimal compactness-loose balance in multiple development pathways;(3)landscape metrics:patch fragmentation decreased by 18.25%,and the internal landscape richness improved by 10.66%compared to the scenario without USM optimization.The findings provide new insight to establish a hierarchical ecological optimization framework as a nature-based spatial protocol to reconcile metropolitan growth with landscape sustainability. 展开更多
关键词 urban spatial morphology ecological network multi-level coupling scenarios simulation urban expansion
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Balaban index of bicyclic chain graphs
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作者 LV Xue-zheng MA Meng-yu WANG Cheng-rui 《Applied Mathematics(A Journal of Chinese Universities)》 2026年第1期194-213,共20页
Chain graphs are{2K_(2),C_(3),C_(5)}-free graphs.Balaban index and sum-Balaban index are two important topological indices.In this paper,we concentrate on the subclass of bicyclic connected chain graphs,identifying th... Chain graphs are{2K_(2),C_(3),C_(5)}-free graphs.Balaban index and sum-Balaban index are two important topological indices.In this paper,we concentrate on the subclass of bicyclic connected chain graphs,identifying the extremal graphs that exhibit the minimum or maximum Balaban index and sum-Balaban index within this class.Moreover,we provide a systematic ordering of all bicyclic connected chain graphs according to the magnitude of their Balaban index and sum-Balaban index. 展开更多
关键词 Balaban index sum-Balaban index chain graph
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Impact toughness,crack initiation and propagation mechanism of Ti6422 alloy with multi-level lamellar microstructure
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作者 Jie Shen Zhihao Zhang Jianxin Xie 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期595-609,共15页
The influence of different solution and aging conditions on the microstructure,impact toughness,and crack initiation and propagation mechanisms of the novel α+β titanium alloy Ti6422 was systematically investigated.... The influence of different solution and aging conditions on the microstructure,impact toughness,and crack initiation and propagation mechanisms of the novel α+β titanium alloy Ti6422 was systematically investigated.By adjusting the furnace cooling time after solution treatment and the aging temperature,Ti6422 alloy samples were developed with a multi-level lamellar microstructure,in-cluding microscaleαcolonies and α_(p) lamellae,as well as nanoscale α_(s) phases.Extending the furnace cooling time after solution treatment at 920℃ for 1 h from 240 to 540 min,followed by aging at 600℃ for 6 h,increased the α_(p) lamella content,reduced the α_(s) phase content,expanded theαcolonies and α_(p) lamellae size,and improved the impact toughness from 22.7 to 53.8 J/cm^(2).Additionally,under the same solution treatment,raising the aging temperature from 500 to 700℃ resulted in a decrease in the α_(s) phase content and a growth in the thickness of the α_(p) lamella and α_(s) phase.The impact toughness increased significantly with these changes.Samples with high α_(p) lamellae content or large α_(s) phase size exhibited high crack initiation and propagation energies.Impact deformation caused severe kinking of the α_(p) lamellae in crack initiation and propagation areas,leading to a uniform and high-density kernel average misorientation(KAM)distribu-tion,enhancing plastic deformation coordination and uniformity.Moreover,the multidirectional arrangement of coarserαcolonies and α_(p) lamellae continuously deflect the crack propagation direction,inhibiting crack propagation. 展开更多
关键词 novel titanium alloy multi-level lamellar microstructure impact toughness crack initiation and propagation
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The triglyceride-glucose index shows promise as a novel prognostic marker for advanced hepatocellular carcinoma
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作者 Tao Xu Xu Qi +1 位作者 Fei-Yu Zhao Nian-Song Qian 《World Journal of Gastroenterology》 2026年第2期167-169,共3页
This commentary critically appraises the study by Li et al which pioneered the exploration of the triglyceride-glucose(TyG)index as a prognostic marker in hepatitis B virus-related advanced hepatocellular carcinoma pa... This commentary critically appraises the study by Li et al which pioneered the exploration of the triglyceride-glucose(TyG)index as a prognostic marker in hepatitis B virus-related advanced hepatocellular carcinoma patients undergoing combined camrelizumab and lenvatinib therapy.While we acknowledge the study’s clinical relevance in proposing an easily accessible metabolic biomarker,we delve into the mechanistic plausibility linking insulin resistance to immunotherapy response and angiogenic inhibition.We further critically examine the methodological limitations,including the retrospective design,the populationspecific TyG cut-off value,and unaddressed metabolic confounders.We highlight the imperative for future research to validate its utility across diverse etiologies and treatment settings,and to unravel the underlying immunometabolic pathways. 展开更多
关键词 Triglyceride-glucose index Prognostic marker Advanced hepatocellular carcinoma Camrelizumab Lenvatinib
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Construction of a mental health literacy evaluation index system for adolescents with mental disorders
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作者 Ying-Qiong Ge Xiao-Shuang Ouyang +2 位作者 Zheng-Min Zhu Bi-Can Tan Xiao-Jian Jiang 《World Journal of Psychiatry》 2026年第1期299-311,共13页
BACKGROUND Timely and accurate evaluation of mental disorders in adolescents using appropriate mental health literacy assessment tools is essential for improving their mental health literacy levels.AIM To develop an e... BACKGROUND Timely and accurate evaluation of mental disorders in adolescents using appropriate mental health literacy assessment tools is essential for improving their mental health literacy levels.AIM To develop an evaluation index system for the mental health literacy of adolescent patients with mental disorders,providing a scientific,comprehensive,and reliable tool for the monitoring and intervention of mental health literacy of such patients.METHODS From December 2022 to June 2023,the evaluation index system for mental health literacy of adolescents with mental disorders was developed through literature reviews,semi-structured interviews,expert letter consultations,and the analytic hierarchy process.Based on this index system,a self-assessment questionnaire was compiled and administered to 305 adolescents with mental disorders to test the reliability and validity of the index system.RESULTS The final evaluation index system for mental health literacy of adolescents with mental disorders included 4 first-level indicators,10 second-level indicators,and 52 third-level indicators.The overall Cronbach’sαcoefficient of the index system was 0.957,with a partial reliability of 0.826 and a content validity index of 0.975.The cumulative variance contribution rate of 10 common factors was 66.491%.The correlation coefficients between each dimension and the total questionnaire ranged from 0.672 to 0.724,while the correlation coefficients in each dimension ranged from 0.389 to 0.705.CONCLUSION The evaluation index system for mental health literacy of adolescents with mental disorders,developed in this study,demonstrated notable reliability and validity,making it a valuable tool for evaluating mental health literacy in this population. 展开更多
关键词 Adolescents Mental disorders Mental health literacy Evaluation index system Delphi method
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Repeatability,reproducibility,and agreement regarding measurement of choroidal vascularity index between OCT and OCT angiography
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作者 Mu-Han Zhong Jia-Li Zhang +5 位作者 Ke-Xin Yu Shu-Qi Fan Xue Li Hao Chen Jin-Hua Bao Ying-Ying Huang 《International Journal of Ophthalmology(English edition)》 2026年第3期498-508,共11页
AIM:To explore the repeatability,reproducibility,and agreement in the measurement of the choroidal vascularity index(CVI)for different swept-source optical coherence tomography(OCT)devices and between OCT and OCT angi... AIM:To explore the repeatability,reproducibility,and agreement in the measurement of the choroidal vascularity index(CVI)for different swept-source optical coherence tomography(OCT)devices and between OCT and OCT angiography(OCTA)images.METHODS:Two swept-source OCT imaging systems,VG200I and Topcon DRI OCT Triton,were used to capture OCT and OCTA images in triplicate.The first and third images were taken by one operator,and the second image was taken by another operator.The built-in software was used to calculate the CVI from the OCTA images(CVI-OCTA),and a custom-designed algorithm was used to calculate the CVI from the OCT images(CVI-OCT).Repeatability and reproducibility were assessed with the intraclass correlation coefficient(ICC),and agreement between devices and between OCT and OCTA were evaluated with Bland-Altman analysis.RESULTS:Sixty-eight eyes from 35 adults(17 females)were included in the analysis.The average age of the participants was 23.6±2.3y,with an average spherical equivalent refraction of-3.08±2.47 D and an average AL of 25.21±1.20 mm.Both OCT devices demonstrated high repeatability and reproducibility in measuring the CVI-OCTA(all ICCs>0.894 across five choroidal regions)and CVI-OCT(all ICCs>0.838).Furthermore,the between-device agreement in measuring the CVI-OCT was good[mean difference(MD)ranging from-2.32%to-3.07%],but that in measuring the CVI-OCTA was poor(MD,1.48%to-7.43%).Additionally,the between-imaging agreement(CVI-OCTA versus CVI-OCT)was poor for both devices(Triton,MD,6.05%to 12.68%;VG200I,MD,6.67%to 12.09%).CONCLUSION:Both OCT devices and the two analytical methods demonstrate good stability.The inter-device consistency of CVI-OCT is good,while the inter-device consistency of CVI-OCTA and the consistency between the two analytical methods in the same device are both poor. 展开更多
关键词 choroidal vascularity index optical coherence tomography angiography AGREEMENT
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Local Characterizations of Results on the Normal Index of Subgroups in Finite Groups
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作者 Yubo LV Yangming LI Xiaoxia DONG 《Journal of Mathematical Research with Applications》 2026年第1期33-39,共7页
Let G be a finite group and H a subgroup of G.The normal index of H in G is defined as the order of K/H_(G),where K is a normal supplement of H in G such that|K|is minimal and H_(G)≤K■G.Let p be a prime which divide... Let G be a finite group and H a subgroup of G.The normal index of H in G is defined as the order of K/H_(G),where K is a normal supplement of H in G such that|K|is minimal and H_(G)≤K■G.Let p be a prime which divides the order of a group G.In this paper,some characterizations of G being p-solvable or p-supersolvable were obtained by analyzing the normal index of certain subgroups of G.These results can be viewed as local version of recent results in the literature. 展开更多
关键词 p-solvable group p-supersolvable group normal index maximal subgroup 2-maximal subgroup
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The Brazilian risk assessment severity index score:a novel tool for predicting in-hospital mortality in emergency departments
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作者 Paulo Henrique Reis Negreiros Mariana Rebello Hilgert +3 位作者 Bruno Guerra Maurício de Carvalho Hugo Manuel Paz Morale Gustavo Lenci Marques 《World Journal of Emergency Medicine》 2026年第2期154-161,共8页
BACKGROUND:Rapid identification of patients at risk of clinical deterioration(in-hospital mortality) in emergency settings is essential for timely and appropriate care.Existing prognostic scores,such as the Acute Phys... BACKGROUND:Rapid identification of patients at risk of clinical deterioration(in-hospital mortality) in emergency settings is essential for timely and appropriate care.Existing prognostic scores,such as the Acute Physiology and Chronic Health Evaluation IV(APACHE IV),Simplified Acute Physiology Score 3(SAPS 3),Sequential Organ Failure Assessment(SOFA),and National Early Warning Score 2(NEWS 2),have limitations in emergency scenarios,particularly in resource-limited settings.We aimed to develop a simple and efficient tool tailored to the Brazilian healthcare system.METHODS:This retrospective,multicenter,cohort study analyzed data from 50,709 adult patients admitted to 12 hospitals in southern and southeastern Brazil between 2019 and 2020.The BRASIL score(Brazilian Risk Assessment Severity Index and Length of stay) was constructed using demographic and clinical variables available at admission.Logistic regression was used to determine the weight of each variable,and each variable was assigned a point value based on its β-coefficient and clinical relevance,with thresholds defined according to established medical cutoffs and statistical performance.The score's predictive accuracy was validated using the area under the receiver operating characteristic curve(AUC) with comparative analysis against NEWS 2.RESULTS:The BRASIL score,including age,sex,respiratory rate,heart rate,oxygen saturation,blood pressure,and body temperature,was derived through variables independently associated with in-hospital mortality in a multicenter cohort.The total score was stratified into three risk categories — low(0–3 points),moderate(4–7 points),and high(>7 points) — using observed inflection points in mortality distribution to optimize discrimination.This stratification demonstrated a stepwise increase in mortality rates across categories and the discriminatory performance,with an overall AUC of 0.743(95% CI:0.726–0.761).Compared to NEWS 2(AUC 0.697,95% CI:0.683–0.711),the BRASIL score offered superior early risk identification,supporting timely clinical decisionmaking and resource allocation in the emergency setting.CONCLUSION:The BRASIL score is a novel tool for predicting in-hospital mortality in emergency departments.Its predictive performance and ease of use suggest that it has the potential to improve patient outcomes. 展开更多
关键词 Cohort study Logistic regression Severity index In-hospital mortality Hospital resource management
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Co-exposure of PFASs,PAHs and metals,immune inflammation and triglyceride-glucose index:Exploring associations and mediation effects in children
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作者 Miao Liu Biao Zhang +11 位作者 Yuanyuan Zhang Jie Wang Lei Zhao Wenting Guo Meng Li Huihua Yang Xuefeng Lai Liangle Yang Xiao Meng Cuijuan Wang Zhihu Zhang Xiaomin Zhang 《Journal of Environmental Sciences》 2026年第2期384-393,共10页
The associations of co-exposure to per-and polyfluoroalkyl substances(PFAS),polycyclic aromatic hydrocarbons(PAHs),and metals with children’s glycometabolism and the underlying mechanism of immune inflammation are la... The associations of co-exposure to per-and polyfluoroalkyl substances(PFAS),polycyclic aromatic hydrocarbons(PAHs),and metals with children’s glycometabolism and the underlying mechanism of immune inflammation are largely unclear.We conducted a longitudinal panel study to explore the effects of individual and mixture of 27 contaminants on an emerging surrogate indicator of insulin resistance,triglyceride-glucose index(TyG),and the mediation of immunoglobulins and cytokines in children aged 4–6 years and 11–13 years.The results showed robust associations of perfluorooctanoic acid(PFOA),perfluorononanoic acid(PFNA),perfluoroundecanoic acid(PFUnDA),and arsenic(As)with elevated TyG.The interaction of PFNA with PFOA was significant,showing a synergistic effect on TyG.And combined association of each pair of PFOA,PFNA,and As with TyG were enhanced.Meanwhile,the effect of contaminants mixture on TyG was significant for polyfluoroalkyl substances(PFAS)mixture,of which 6:2 Chlorinated polyfluorinated ether sulfonates(Cl-PFESA),PFNA,and PFUnDA weighted more than others.Notably,contaminants were related to immune globulins and cytokines,of which chemokine ligand(CCL)4,interleukin(IL)-1β,IL-9,and tumor necrosis factor(TNF)-α significantly mediated associations of PFOA,PFNA,and PFUnDA with TyG.Accordingly,PFAS and metals were individually and jointly associated with TyG elevation,with 6:2 Cl-PFESA,PFNA,and PFUnDA contributing the most,and CCL4,IL-1β,IL-9,and TNF-α might be the underlying mediators in children. 展开更多
关键词 Priority-controlled contaminants mixture Triglyceride-glucose index Mediation of immune inflammation Panel study
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Digital light processing 3D printing of ceramics for W-band gradient refractive index metalens
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作者 Wuzhao Li Siqian Wu +2 位作者 Jin Chen Rong Wang Qi Ge 《International Journal of Extreme Manufacturing》 2026年第1期601-616,共16页
Gradient refractive index(GRIN)metalenses are increasingly valued in high-frequency communication due to their exceptional radiation performance.Ceramics with high dielectric constants and low dielectric losses are id... Gradient refractive index(GRIN)metalenses are increasingly valued in high-frequency communication due to their exceptional radiation performance.Ceramics with high dielectric constants and low dielectric losses are ideal candidates for GRIN metalenses.Digital light processing(DLP)3D printing provides a feasible and efficient approach for manufacturing ceramic GRIN metalenses.However,the scattering of ultraviolet(UV)light by ceramic particles in the slurry reduces the printing accuracy of DLP technology,making it difficult to achieve the intricate structural features required for GRIN metalenses in high-frequency communication.In this work,we propose an approach to improve printing accuracy by optimizing the ceramic slurry composition and implementing a dimensional compensation design strategy.Utilizing geometric optics and the S-parameter inversion method,we design a GRIN metalens consisting of two distinct types of subwavelength unit cells(Y-shaped and circular hole geometries)with a minimum feature size of 160μm.Through a refined slurry formulation and precise design parameter compensation,high-fidelity ceramic GRIN metalenses are successfully fabricated.The fabricated metalens exhibits a maximum gain enhancement of 18.4 dBi and a deflection angle of±30°over a bandwidth of 37.84% in the W-band(75-110 GHz).The highly directional far-field beam radiation and efficient beam steering capabilities highlight the potential of ceramic GRIN metalenses for applications in satellite communications,radar systems,and other high-frequency technologies. 展开更多
关键词 3D printing CERAMICS digital light processing gradient refractive index metalens
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INDEX数控多轴车床有效应对无铅黄铜材料加工带来的技术挑战
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作者 《现代制造》 2026年第3期74-75,共2页
数控多轴车床的核心优势在于较短的加工节拍以及强大的多工序加工能力,能够高精度加工复杂零件,即使面对无铅黄铜等难加工材料,亦能实现高效稳定的加工。INDEX数控多轴车床在多个技术维度上已显著超越传统的凸轮多轴车床。这一结论得到... 数控多轴车床的核心优势在于较短的加工节拍以及强大的多工序加工能力,能够高精度加工复杂零件,即使面对无铅黄铜等难加工材料,亦能实现高效稳定的加工。INDEX数控多轴车床在多个技术维度上已显著超越传统的凸轮多轴车床。这一结论得到了精密车削零件制造商Firner Trautwein公司的验证,该公司在德国Zeil am Main及Dunningen的生产基地均使用INDEX数控多轴车床,并表示其生产能力已为应对未来市场需求做好了充分准备。 展开更多
关键词 无铅黄铜 多工序加工 index数控多轴车床
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Highly sensitive,multi-stage,and mid-infrared refractive index sensor based on photonic spin Hall effect
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作者 Jiaye Ding Chenglong Wang +2 位作者 Shengli Liu Peng Dong Jie Cheng 《Chinese Physics B》 2026年第1期432-438,共7页
Surface polaritons,as surface electromagnetic waves propagating along the surface of a medium,have played a crucial role in enhancing photonic spin Hall effect(PSHE)and developing highly sensitive refractive index(RI)... Surface polaritons,as surface electromagnetic waves propagating along the surface of a medium,have played a crucial role in enhancing photonic spin Hall effect(PSHE)and developing highly sensitive refractive index(RI)sensors.Among them,the traditional surface plasmon polariton(SPP)based on noble metals limits its application beyond the near-infrared(IR)regime due to the large negative permittivity and optical losses.In this contribution,we theoretically proposed a highly sensitive PSHE sensor with the structure of Ge prism-SiC-Si:InAs-sensing medium,by taking advantage of the hybrid surface plasmon phonon polariton(SPPhP)in mid-IR regime.Here,heavily Si-doped InAs(Si:InAs)and SiC excite the SPP and surface phonon polariton(SPhP),and the hybrid SPPhP is realized in this system.More importantly,the designed PSHE sensor based on this SPPhP mechanism achieves the multi-stage RI measurements from 1.00025-1.00225 to 1.70025-1.70225,and the maximal intensity sensitivity and angle sensitivity can be up to 9.4×10^(4)μm/RIU and245°/RIU,respectively.These findings provide a new pathway for the enhancement of PSHE in mid-IR regime,and offer new opportunities to develop highly sensitive RI sensors in multi-scenario applications,such as harmful gas monitoring and biosensing. 展开更多
关键词 refractive index(RI)sensor photonic spin Hall effect MID-IR MULTI-STAGE
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Building collapse prediction due to earthquakes through ML algorithm:Hybrid methodology based on past-earthquake damage reports and resilience index
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作者 Alvaro Hurtado Hector Aroquipa +2 位作者 David Restrepo Francisco Nieto Julian Carrillo 《Resilient Cities and Structures》 2026年第1期102-117,共16页
This study presents a hybrid methodology for predicting building collapses within the Intelligent Circular Resilience(ICR)framework.This uses a supervised Machine Learning(ML)approach,earthquake damage re-ports,and th... This study presents a hybrid methodology for predicting building collapses within the Intelligent Circular Resilience(ICR)framework.This uses a supervised Machine Learning(ML)approach,earthquake damage re-ports,and the Simplified Resilience Index(SRI),derived from existing earthquake damage models(EDM)-based on fragility and vulnerability functions-used in the probabilistic seismic risk assessment(PSRA).A curated building damage database comprising 89 structures(71 collapsed and 18 non-collapsed)from ten countries affected by major earthquakes(Mw 6.1-8.1,epicentral distances of 3-125 km,and PGA values ranging from 0.14 g to 0.82 g)was developed,including attributes related to exposure:occupancy,main structural material,number of stories,construction year,and hazard:magnitude,epicentral distance,intensity measures(Peak-ground acceleration,PGA,and elastic spectral acceleration).The dataset includes events such as the 2017 Puebla-Morelos earthquake(Mw 7.1,Mexico),the 1999 Kocaeli earthquake(Mw 7.6,Turkey),and the 2011 Christchurch earthquake(Mw 6.1,New Zealand),among others.Likewise,dependent attributes such as time elapsed and SRI(under 120-,180-,and 365-day recovery scenarios)were calculated using 2-EDMs.Eight Random Forest models were trained and tested for collapse and non-collapse classification using combinations of independent and dependent attributes.The results indicate that models incorporating exposure-related varia-bles-such as structural material,number of stories,construction year,and occupancy-alongside the SRI significantly improve collapse classification performance,achieving recall and F1 scores above 95%.Notably,many collapsed buildings exhibited low intensities(PGA≤0.25 g),emphasizing the influence of local site effects-particularly in Mexico City.The findings demonstrate that incorporating SRI enhances the reliability of collapse prediction and supports its use as an interpretable resilience proxy during early ICR stages.This hybrid methodology bridges empirical data,traditional PSRA models,and ML techniques,contributing to more accurate and scalable post-earthquake resilience assessments. 展开更多
关键词 Seismic resilience Simplified resilience index Machine learning Fragility and vulnerability functions Collapse prediction
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A Multi-Level Semantic Constraint Approach for Highway Tunnel Scene Twin Modeling 被引量:2
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作者 LI Yufei XIE Yakun +3 位作者 CHEN Mingzhen ZHAO Yaoji TU Jiaxing HU Ya 《Journal of Geodesy and Geoinformation Science》 2025年第2期37-56,共20页
As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods ge... As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods generally have problems such as insufficient 3D scene description capability and low dynamic update efficiency,which are difficult to meet the demand of real-time accurate management.For this reason,this paper proposes a vehicle twin modeling method for road tunnels.This approach starts from the actual management needs,and supports multi-level dynamic modeling from vehicle type,size to color by constructing a vehicle model library that can be flexibly invoked;at the same time,semantic constraint rules with geometric layout,behavioral attributes,and spatial relationships are designed to ensure that the virtual model matches with the real model with a high degree of similarity;ultimately,the prototype system is constructed and the case region is selected for the case study,and the dynamic vehicle status in the tunnel is realized by integrating real-time monitoring data with semantic constraints for precise virtual-real mapping.Finally,the prototype system is constructed and case experiments are conducted in selected case areas,which are combined with real-time monitoring data to realize dynamic updating and three-dimensional visualization of vehicle states in tunnels.The experiments show that the proposed method can run smoothly with an average rendering efficiency of 17.70 ms while guaranteeing the modeling accuracy(composite similarity of 0.867),which significantly improves the real-time and intuitive tunnel management.The research results provide reliable technical support for intelligent operation and emergency response of road tunnels,and offer new ideas for digital twin modeling of complex scenes. 展开更多
关键词 highway tunnel twin modeling multi-level semantic constraints tunnel vehicles multidimensional modeling
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Research on Multi-Level Automatic Filling Optimization Design Method for Layered Cross-Sectional Layout of Umbilical 被引量:1
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作者 YIN Xu FAN Zhi-rui +4 位作者 CAO Dong-hui LIU Yu-jie LI Meng-shu YAN Jun YANG Zhi-xun 《China Ocean Engineering》 2025年第5期891-903,共13页
The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly comple... The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly complex layout combinations.Furthermore,due to constraints in component quantity and geometry within the cross-sectional layout,filler bodies must be incorporated to maintain cross-section performance.Conventional design approaches based on manual experience suffer from inefficiency,high variability,and difficulties in quantification.This paper presents a multi-level automatic filling optimization design method for umbilical cross-sectional layouts to address these limitations.Initially,the research establishes a multi-objective optimization model that considers compactness,balance,and wear resistance of the cross-section,employing an enhanced genetic algorithm to achieve a near-optimal layout.Subsequently,the study implements an image processing-based vacancy detection technique to accurately identify cross-sectional gaps.To manage the variability and diversity of these vacant regions,the research introduces a multi-level filling method that strategically selects and places filler bodies of varying dimensions,overcoming the constraints of uniform-size fillers.Additionally,the method incorporates a hierarchical strategy that subdivides the complex cross-section into multiple layers,enabling layer-by-layer optimization and filling.This approach reduces manufac-turing equipment requirements while ensuring practical production process feasibility.The methodology is validated through a specific umbilical case study.The results demonstrate improvements in compactness,balance,and wear resistance compared with the initial cross-section,offering novel insights and valuable references for filler design in umbilical cross-sections. 展开更多
关键词 UMBILICAL cross-sectional layout multi-level filling layered layout optimization design
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Prognostic value of the preoperative systemic immune-inflammation nutritional index in patients with gastric cancer 被引量:1
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作者 Li-Jing Wang Cai-Lu Lei +7 位作者 Ting-An Wang Zhi-Feng Lin Shi-Jie Feng Tao Wei Yan-Qin Li Meng-Ru Shen Yan Li Liu-Feng Liao 《World Journal of Clinical Oncology》 2025年第4期130-141,共12页
BACKGROUND Gastric cancer(GC)is the fifth most common cancer and the third leading cause of cancer-related deaths in China.Many patients with GC frequently experience symptoms related to the disease,including anorexia... BACKGROUND Gastric cancer(GC)is the fifth most common cancer and the third leading cause of cancer-related deaths in China.Many patients with GC frequently experience symptoms related to the disease,including anorexia,nausea,vomiting,and other discomforts,and often suffer from malnutrition,which in turn negatively affects perioperative safety,prognosis,and the effectiveness of adjuvant therapeutic measures.Consequently,some nutritional indicators such as nutritional risk index(NRI),prognostic nutritional index(PNI),and systemic immune-inflammatorynutritional index(SIINI)can be used as predictors of the prognosis of GC patients.AIM To examine the prognostic significance of PNI,NRI,and SIINI in postoperative patients with GC.METHODS A retrospective analysis was conducted on the clinical data of patients with GC who underwent surgical treatment at the Guangxi Medical University Cancer Hospital between January 2010 and December 2018.The area under the receiver operating characteristic(ROC)curve was assessed using ROC curve analysis,and the optimal cutoff values for NRI,PNI,and SIINI were identified using the You-Review-HTMLden index.Survival analysis was performed using the Kaplan-Meier method.In addition,univariate and multivariate analyses were conducted using the Cox proportional hazards regression model.RESULTS This study included a total of 803 patients.ROC curves were used to evaluate the prognostic ability of NRI,PNI,and SIINI.The results revealed that SIINI had superior predictive accuracy.Survival analysis indicated that patients with GC in the low SIINI group had a significantly better survival rate than those in the high SIINI group(P<0.05).Univariate analysis identified NRI[hazard ratio(HR)=0.68,95%confidence interval(CI):0.52-0.89,P=0.05],PNI(HR=0.60,95%CI:0.46-0.79,P<0.001),and SIINI(HR=2.10,95%CI:1.64-2.69,P<0.001)as prognostic risk factors for patients with GC.However,multifactorial analysis indicated that SIINI was an independent risk factor for the prognosis of patients with GC(HR=1.65,95%CI:1.26-2.16,P<0.001).CONCLUSION Analysis of clinical retrospective data revealed that SIINI is a valuable indicator for predicting the prognosis of patients with GC.Compared with NRI and PNI,SIINI may offer greater application for prognostic assessment. 展开更多
关键词 Systemic immune-inflammatory-nutritional index Prognostic nutritional index Nutritional risk index Gastric cancer Prognosis
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基于ARIMA与Theil Index的瓦斯异常涌出态势评估
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作者 李作泉 张巨峰 +3 位作者 权继业 张建江 苗在全 王玉峰 《陇东学院学报》 2025年第5期5-10,共6页
为了更好地进行瓦斯异常涌出预测与预警,应用自回归积分滑动平均(ARIMA)模型与泰尔指数(Theil Index)模型相结合,以甘肃某矿东1102工作面为例,结合历史数据,分别在不同时间尺度下进行了参数优化,选取ARIMA(1,1,1)作为最佳模型,利用Theil... 为了更好地进行瓦斯异常涌出预测与预警,应用自回归积分滑动平均(ARIMA)模型与泰尔指数(Theil Index)模型相结合,以甘肃某矿东1102工作面为例,结合历史数据,分别在不同时间尺度下进行了参数优化,选取ARIMA(1,1,1)作为最佳模型,利用Theil Index模型构建了瓦斯涌出量的综合评价指标,对瓦斯异常涌出态势进行了综合分析。通过ARIMA(1,1,1)模型,预测了工作面瓦斯涌出的动态趋势,结合泰尔指数对潜在的异常态势进行了识别和分析,并提出了相应的瓦斯异常涌出防治措施。研究结果表明,ARIMA模型与Theil Index模型联合可以有效地预测和评估瓦斯异常涌出态势,为煤矿安全管理提供了新的方法。 展开更多
关键词 ARIMA模型 Theil index模型 瓦斯异常涌出 趋势预测
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