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基于COM-B模型的饮食管理在经皮冠状动脉介入治疗老年病人中的应用
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作者 王畅 王飞 +4 位作者 朱宁宁 林昕 王琳 蔡维维 吴玲玲 《蚌埠医科大学学报》 2026年第1期120-125,131,共7页
目的:探讨基于COM-B模型的饮食管理在经皮冠状动脉介入治疗(PCI)老年病人中的应用效果。方法:采用便利抽样法选取行PCI老年病人74例为研究对象,随机数字表法分为对照组和干预组,各37例。对照组接受常规饮食护理,干预组实施基于COM-B模... 目的:探讨基于COM-B模型的饮食管理在经皮冠状动脉介入治疗(PCI)老年病人中的应用效果。方法:采用便利抽样法选取行PCI老年病人74例为研究对象,随机数字表法分为对照组和干预组,各37例。对照组接受常规饮食护理,干预组实施基于COM-B模型的饮食管理。比较2组病人干预前及干预6周后的饮食健康行为得分、饮食结构、血脂指标和体质量指数(BMI)、体脂率(BF%)。结果:干预6周后,干预组饮食健康行为得分明显高于对照组(P<0.01);饮食结构中干预组谷类摄入量低于对照组(P<0.05),全谷物、水果、大豆和坚果摄入量均高于对照组(P<0.05~P<0.01);干预组总胆固醇、低密度脂蛋白胆固醇水平均低于对照组(P<0.01和P<0.05);干预组BMI、BF%均低于对照组(P<0.05)。结论:基于COM-B模型的饮食管理能够促进PCI术后病人饮食健康行为,有助于改善病人饮食结构和BMI、BF%及血脂指标,促进病人康复。 展开更多
关键词 经皮冠状动脉介入治疗 冠心病 老年 com-b模型 饮食管理
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基于COM-B模型癌症患者口服营养补充剂依从性影响因素的系统评价
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作者 郝妩媚 台靖宇 +2 位作者 王雯静 李若琳 郭爱敏 《护理学报》 2026年第4期24-29,共6页
目的系统评价癌症患者口服营养补充剂(oral nutritional supplements,ONS)依从性的影响因素,为未来制订ONS依从性干预策略提供依据。方法系统检索PubMed、Embase、CINAHL、Web of Science、The Cochrance library、中国知网、中国生物... 目的系统评价癌症患者口服营养补充剂(oral nutritional supplements,ONS)依从性的影响因素,为未来制订ONS依从性干预策略提供依据。方法系统检索PubMed、Embase、CINAHL、Web of Science、The Cochrance library、中国知网、中国生物医学文献数据库、万方数据库、维普中文科技期刊数据库中癌症患者ONS依从性影响因素相关研究,检索时限为建库至2025年3月15日。由2名研究者独立进行文献筛选,遵循乔安娜·布里格斯研究所循证卫生保健中心混合方法系统评价指南,采用混合方法系统评价工具混合方法系统评价工具进行质量评价,基于能力、机会、动机和行为模型对癌症患者ONS依从性的影响因素进行分析。结果共纳入11项研究。整合结果显示:癌症患者ONS依从性的影响因素包括能力因素(ONS不良反应、体质量、饮食摄入减少、疾病及治疗因素、ONS及营养知识、固定ONS的服用时间)、机会因素(每日餐次、ONS制剂特性、明确ONS目标摄入量、社会支持、主要照顾者)和动机因素(自我效能、感知必要性、服药信念、服药动机)。结论癌症患者ONS依从性受到多维度、多层次影响因素的综合影响。未来干预策略的制定应从多角度出发,提供高质量健康教育与营养指导,通过心理干预强化动机,提升患者营养知识与自我管理技能,并优化其外部机会,进而提升其ONS依从性。 展开更多
关键词 癌症 口服营养补充剂 依从性 com-b模型 系统评价
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基于COM-B模型构建“微正念+低FODMAP饮食指导”协同干预方案对IBS-D患者焦虑与腹泻的影响
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作者 江敬红 《视周刊》 2026年第6期122-123,共2页
腹泻型肠易激综合征(Irritable Bowel Syndrome with Diarrhea,IBS-D)是一种常见的功能性胃肠病,以反复发作的腹痛、腹胀、腹泻为核心症状,常伴随焦虑、抑郁等心理问题。低FODMAP饮食通过限制难吸收碳水化合物,可减少肠道产气与刺激,有... 腹泻型肠易激综合征(Irritable Bowel Syndrome with Diarrhea,IBS-D)是一种常见的功能性胃肠病,以反复发作的腹痛、腹胀、腹泻为核心症状,常伴随焦虑、抑郁等心理问题。低FODMAP饮食通过限制难吸收碳水化合物,可减少肠道产气与刺激,有效缓解IBS-D腹泻症状;微正念训练则能调节自主神经功能,减轻焦虑情绪,改善脑-肠轴失衡。COM-B模型(CaPability-OPPortunity-Motivation-Behavior)从能力、机会、动机三个维度解析行为改变机制,为多维度干预方案的构建提供了科学框架。本研究基于COM-B模型,整合微正念训练与低FODMAP饮食指导,构建协同干预方案,通过精准识别患者行为改变障碍,实现个性化干预,旨在为IBS-D患者提供更有效的非药物干预策略。现将效果分析如下。 展开更多
关键词 腹泻 低FODMAP饮食 com-b模型 IBS-D 焦虑
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基于COM-B模型的叙事护理干预方案在急性心肌梗死患者中的应用
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作者 陆梦青 冯丹 张怡红 《当代护士(下旬刊)》 2026年第1期113-119,共7页
目的 探讨基于能力、机会、动机-行为(Capability,Opportunity,Motivation and Behaviour,COM-B)模型的叙事护理干预方案在急性心肌梗死(acute myocardial infarction,AMI)患者中的应用效果。方法 2023年5月-2024年5月,选取本院收治的96... 目的 探讨基于能力、机会、动机-行为(Capability,Opportunity,Motivation and Behaviour,COM-B)模型的叙事护理干预方案在急性心肌梗死(acute myocardial infarction,AMI)患者中的应用效果。方法 2023年5月-2024年5月,选取本院收治的96例AMI患者为研究对象,采用随机数字表法将患者分为观察组和对照组,每组各48例。对照组实施常规护理干预,观察组在对照组的基础上实施基于COM-B模型的叙事护理干预方案,比较两组干预前后的自我护理能力、心功能指标及生活质量改善情况,并记录两组不良心血管事件的发生率。结果 干预后,观察组自我护理能力量表(Exercise of Self-Care Agency Scale,ESCA)总分及各维度评分均高于对照组(P<0.05);干预后,观察组的左室射血分数(left ventricular ejection fraction,LVEF)及二尖瓣血流频谱E峰与A峰的比值均大于对照组,6 min步行试验距离远于对照组(P<0.05);干预后,观察组的不良心血管事件发生率为4.17%,低于对照组的20.83%(P<0.05);干预后,观察组的中国心血管病人生活质量评定问卷(China Questionnaire of Quality of Life in Patients with Cardiovascular Diseases,CQQC)总分及各维度评分高于对照组(P<0.05)。结论 基于COM-B模型的叙事护理干预方案能有效提升AMI患者的自我护理能力,改善其心功能,有助于预防不良心血管事件的发生,并提升患者的生活质量。 展开更多
关键词 com-b模型 叙事护理 急性心肌梗死 自我护理能力
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Agri-Eval:Multi-level Large Language Model Valuation Benchmark for Agriculture
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作者 WANG Yaojun GE Mingliang +2 位作者 XU Guowei ZHANG Qiyu BIE Yuhui 《农业机械学报》 北大核心 2026年第1期290-299,共10页
Model evaluation using benchmark datasets is an important method to measure the capability of large language models(LLMs)in specific domains,and it is mainly used to assess the knowledge and reasoning abilities of LLM... Model evaluation using benchmark datasets is an important method to measure the capability of large language models(LLMs)in specific domains,and it is mainly used to assess the knowledge and reasoning abilities of LLMs.Therefore,in order to better assess the capability of LLMs in the agricultural domain,Agri-Eval was proposed as a benchmark for assessing the knowledge and reasoning ability of LLMs in agriculture.The assessment dataset used in Agri-Eval covered seven major disciplines in the agricultural domain:crop science,horticulture,plant protection,animal husbandry,forest science,aquaculture science,and grass science,and contained a total of 2283 questions.Among domestic general-purpose LLMs,DeepSeek R1 performed best with an accuracy rate of 75.49%.In the realm of international general-purpose LLMs,Gemini 2.0 pro exp 0205 standed out as the top performer,achieving an accuracy rate of 74.28%.As an LLMs in agriculture vertical,Shennong V2.0 outperformed all the LLMs in China,and the answer accuracy rate of agricultural knowledge exceeded that of all the existing general-purpose LLMs.The launch of Agri-Eval helped the LLM developers to comprehensively evaluate the model's capability in the field of agriculture through a variety of tasks and tests to promote the development of the LLMs in the field of agriculture. 展开更多
关键词 large language models assessment systems agricultural knowledge agricultural datasets
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Ecological Dynamics of a Logistic Population Model with Impulsive Age-selective Harvesting
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作者 DAI Xiangjun JIAO Jianjun 《应用数学》 北大核心 2026年第1期72-79,共8页
In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asy... In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asymptotic stability of the trivial solution and the positive periodic solution.Finally,numerical simulations are presented to validate our results.Our results show that age-selective harvesting is more conducive to sustainable population survival than non-age-selective harvesting. 展开更多
关键词 The logistic population model Selective harvesting Asymptotic stability EXTINCTION
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Ecosystem service models are indeed being validated:A response to Pereira et al.(2025)
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作者 James M.Bullock Danny A.P.Hooftman +1 位作者 John W.Redhead Simon Willcock 《Geography and Sustainability》 2026年第1期247-248,共2页
In their recent paper Pereira et al.(2025)claim that validation is overlooked in mapping and modelling of ecosystem services(ES).They state that“many studies lack critical evaluation of the results and no validation ... In their recent paper Pereira et al.(2025)claim that validation is overlooked in mapping and modelling of ecosystem services(ES).They state that“many studies lack critical evaluation of the results and no validation is provided”and that“the validation step is largely overlooked”.This assertion may have been true several years ago,for example,when Ochoa and Urbina-Cardona(2017)made a similar observation.However,there has been much work on ES model validation over the last decade. 展开更多
关键词 evaluation MAPPING modeling es model ecosystem services VALIDATION
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Modeling of Precipitation over Africa:Progress,Challenges,and Prospects
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作者 A.A.AKINSANOLA C.N.WENHAJI +21 位作者 R.BARIMALALA P.-A.MONERIE R.D.DIXON A.T.TAMOFFO M.O.ADENIYI V.ONGOMA I.DIALLO M.GUDOSHAVA C.M.WAINWRIGHT R.JAMES K.C.SILVERIO A.FAYE S.S.NANGOMBE M.W.POKAM D.A.VONDOU N.C.G.HART I.PINTO M.KILAVI S.HAGOS E.N.RAJAGOPAL R.K.KOLLI S.JOSEPH 《Advances in Atmospheric Sciences》 2026年第1期59-86,共28页
In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and cha... In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and change.Likewise,this period has seen a significant increase in our understanding of the physical processes and mechanisms that drive precipitation and its variability across different regions of Africa.By leveraging a large volume of climate model outputs,numerous studies have investigated the model representation of African precipitation as well as underlying physical processes.These studies have assessed whether the physical processes are well depicted and whether the models are fit for informing mitigation and adaptation strategies.This paper provides a review of the progress in precipitation simulation overAfrica in state-of-the-science climate models and discusses the major issues and challenges that remain. 展开更多
关键词 RAINFALL MONSOON climate modeling CORDEX CMIP6 convection-permitting models
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Stability of k-ε model in Kolmogorov flow
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作者 Jiashuo GUO Le FANG 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期165-184,共20页
The Reynolds-averaged Navier-Stokes(RANS)technique enables critical engineering predictions and is widely adopted.However,since this iterative computation relies on the fixed-point iteration,it may converge to unexpec... The Reynolds-averaged Navier-Stokes(RANS)technique enables critical engineering predictions and is widely adopted.However,since this iterative computation relies on the fixed-point iteration,it may converge to unexpected non-physical phase points in practice.We conduct an analysis on the phase-space characteristics and the fixed-point theory underlying the k-ε turbulence model,and employ the classical Kolmogorov flow as a framework,leveraging its direct numerical simulation(DNS)data to construct a one-dimensional(1D)system under periodic/fixed boundary conditions.The RANS results demonstrate that under periodic boundary conditions,the k-ε model exhibits only a unique trivial fixed point,with asymptotes capturing the phase portraits.The stability of this trivial fixed point is determined by a mathematically derived stability phase diagram,indicating the fact that the k-ε model will never converge to correct values under periodic conditions.In contrast,under fixed boundary conditions,the model can yield a stable non-trivial fixed point.The evolutionary mechanisms and their relationship with boundary condition settings systematically explain the inherent limitations of the k-ε model,i.e.,its deficiency in computing the flow field under periodic boundary conditions and sensitivity to boundary-value specifications under fixed boundary conditions.These conclusions are finally validated with the open-source code OpenFOAM. 展开更多
关键词 k-εmodel Kolmogorov flow INSTABILITY turbulence model
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Design optimization and FEA of B-6 and B-7 levels ballistics armor:A modelling approach
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作者 Muhammad Naveed CHU Jinkui +1 位作者 Atif Ur Rehman Arsalan Hyder 《大连理工大学学报》 北大核心 2026年第1期66-77,共12页
Utilizing finite element analysis,the ballistic protection provided by a combination of perforated D-shaped and base armor plates,collectively referred to as radiator armor,is evaluated.ANSYS Explicit Dynamics is empl... Utilizing finite element analysis,the ballistic protection provided by a combination of perforated D-shaped and base armor plates,collectively referred to as radiator armor,is evaluated.ANSYS Explicit Dynamics is employed to simulate the ballistic impact of 7.62 mm armor-piercing projectiles on Aluminum AA5083-H116 and Steel Secure 500 armors,focusing on the evaluation of material deformation and penetration resistance at varying impact points.While the D-shaped armor plate is penetrated by the armor-piercing projectiles,the combination of the perforated D-shaped and base armor plates successfully halts penetration.A numerical model based on the finite element method is developed using software such as SolidWorks and ANSYS to analyze the interaction between radiator armor and bullet.The perforated design of radiator armor is to maintain airflow for radiator function,with hole sizes smaller than the bullet core diameter to protect radiator assemblies.Predictions are made regarding the brittle fracture resulting from the projectile core′s bending due to asymmetric impact,and the resulting fragments failed to penetrate the perforated base armor plate.Craters are formed on the surface of the perforated D-shaped armor plate due to the impact of projectile fragments.The numerical model accurately predicts hole growth and projectile penetration upon impact with the armor,demonstrating effective protection of the radiator assemblies by the radiator armor. 展开更多
关键词 radiator armor ballistics simulation Johnson-Cook model armor-piercing projectile perforated D-shaped armor plate
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CIT-Rec:Enhancing Sequential Recommendation System with Large Language Models
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作者 Ziyu Li Zhen Chen +2 位作者 Xuejing Fu Tong Mo Weiping Li 《Computers, Materials & Continua》 2026年第3期2328-2343,共16页
Recommendation systems are key to boosting user engagement,satisfaction,and retention,particularly on media platforms where personalized content is vital.Sequential recommendation systems learn from user-item interact... Recommendation systems are key to boosting user engagement,satisfaction,and retention,particularly on media platforms where personalized content is vital.Sequential recommendation systems learn from user-item interactions to predict future items of interest.However,many current methods rely on unique user and item IDs,limiting their ability to represent users and items effectively,especially in zero-shot learning scenarios where training data is scarce.With the rapid development of Large Language Models(LLMs),researchers are exploring their potential to enhance recommendation systems.However,there is a semantic gap between the linguistic semantics of LLMs and the collaborative semantics of recommendation systems,where items are typically indexed by IDs.Moreover,most research focuses on item representations,neglecting personalized user modeling.To address these issues,we propose a sequential recommendation framework using LLMs,called CIT-Rec,a model that integrates Collaborative semantics for user representation and Image and Text information for item representation to enhance Recommendations.Specifically,by aligning intuitive image information with text containing semantic features,we can more accurately represent items,improving item representation quality.We focus not only on item representations but also on user representations.To more precisely capture users’personalized preferences,we use traditional sequential recommendation models to train on users’historical interaction data,effectively capturing behavioral patterns.Finally,by combining LLMs and traditional sequential recommendation models,we allow the LLM to understand linguistic semantics while capturing collaborative semantics.Extensive evaluations on real-world datasets show that our model outperforms baseline methods,effectively combining user interaction history with item visual and textual modalities to provide personalized recommendations. 展开更多
关键词 Large language models vision language models sequential recommendation instruction tuning
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Lithospheric magnetic variations on the Tibetan Plateau based on a 3D surface spline model,compared with strong earthquake occurrences
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作者 PengTao Zhang Jun Yang +3 位作者 LiLi Feng Xia Li YuHong Zhao YingFeng Ji 《Earth and Planetary Physics》 2026年第1期30-43,共14页
The National Geophysical Data Center(NGDC)of the United States has collected aeromagnetic data for input into a series of geomagnetic models to improve model resolution;however,in the Tibetan Plateau region,ground-bas... The National Geophysical Data Center(NGDC)of the United States has collected aeromagnetic data for input into a series of geomagnetic models to improve model resolution;however,in the Tibetan Plateau region,ground-based observations remain insufficient to clearly reflect the characteristics of the region’s lithospheric magnetism.In this study,we evaluate the lithospheric magnetism of the Tibetan Plateau by using a 3D surface spline model based on observations from>200 newly constructed repeat stations(portable stations)to determine the spatial distribution of plateau geomagnetism,as well as its correlation with the tectonic features of the region.We analyze the relationships between M≥5 earthquakes and lithospheric magnetic field variations on the Tibetan Plateau and identify regions susceptible to strong earthquakes.We compare the geomagnetic results with those from an enhanced magnetic model(EMM2015)developed by the NGDC and provide insights into improving lithospheric magnetic field calculations in the Tibetan Plateau region.Further research reveals that these magnetic anomalies exhibit distinct differences from the magnetic-seismic correlation mechanisms observed in other tectonic settings;here,they are governed primarily by the combined effects of compressional magnetism,thermal magnetism,and deep thermal stress.This study provides new evidence of geomagnetic anomalies on the Tibetan Plateau,interprets them physically,and demonstrates their potential for identifying seismic hazard zones on the Plateau. 展开更多
关键词 Tibetan Plateau magnetic variation SEISMICITY surface spline model enhanced magnetic model
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UAV-to-Ground Channel Modeling:(Quasi-)Closed-Form Channel Statistics and Manual Parameter Estimation
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作者 Zeng Linzhou Liao Xuewen +3 位作者 Xie Wenwu Ma Zhangfeng Xiong Baiping Jiang Hao 《China Communications》 2026年第1期47-66,共20页
(Quasi-)closed-form results for the statistical properties of unmanned aerial vehicle(UAV)airto-ground channels are derived for the first time using a novel spatial-vector-based method from a threedimensional(3-D)arbi... (Quasi-)closed-form results for the statistical properties of unmanned aerial vehicle(UAV)airto-ground channels are derived for the first time using a novel spatial-vector-based method from a threedimensional(3-D)arbitrary-elevation one-cylinder model.The derived results include a closed-form expression for the space-time correlation function and some quasi-closed-form ones for the space-Doppler power spectrum density,the level crossing rate,and the average fading duration,which are shown to be the generalizations of those previously obtained from the two-dimensional(2-D)one-ring model and the 3-D low-elevation one-cylinder model for terrestrial mobile-to-mobile channels.The close agreements between the theoretical results and the simulations as well as the measurements validate the utility of the derived channel statistics.Based on the derived expressions,the impacts of some parameters on the channel characteristics are investigated in an effective,efficient,and explicable way,which leads to a general guideline on the manual parameter estimation from the measurement description. 展开更多
关键词 channel characteristics geometry-based stochastic model manual parameter estimation UAV channel modeling
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Ecological restoration model selection for abandoned mines in the Luo River Basin,Eastern Qinling Mountains
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作者 HUANG Yuming GAO Ningze +1 位作者 ZHANG Hanyuan ZHENG Wenlong 《Journal of Mountain Science》 2026年第1期358-369,共12页
Effective management of mining areas in the Luo River Basin,located in the eastern Qinling Mountains,is vital for the integrated protection and restoration needed to support the high-quality development of the Yellow ... Effective management of mining areas in the Luo River Basin,located in the eastern Qinling Mountains,is vital for the integrated protection and restoration needed to support the high-quality development of the Yellow River Basin.Using the‘cupball'model,this study analyzes the limiting factors and restoration characteristics across four mining areas and proposes a conceptual model for selecting appropriate restoration approaches.A second conceptual model is then introduced to address regional development needs,incorporating ecological conservation,safety protection,and people's wellbeing.The applicability of the integrated model selection framework is demonstrated through a case study on the south bank of the Qinglongjian River.The results indicate that:(1)The key limiting factors are similar across cases,but the degree of ecological degradation varies.(2)Mildly degraded areas are represented by a shallower and narrower‘cup',where natural recovery is the preferred approach,whereas moderately and severely degraded systems call for assisted regeneration and ecological reconstruction,respectively.(3)When the restoration models determined based on limiting factors and development needs are consistent,the model is directly applicable;if they differ,the option involving less artificial intervention is preferred;(4)Monitoring of the restored mining area on the Qinglongjian River's south bank confirms significant improvements in soil erosion control and vegetation coverage.This study provides a transferable methodology for balancing resource extraction with ecosystem conservation,offering practical insights for other ecologically vulnerable mining regions. 展开更多
关键词 Luo River Basin Cup-ball model Mine restoration Ecological degradation Conceptual model Development needs
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Do Higher Horizontal Resolution Models Perform Better?
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作者 Shoji KUSUNOKI 《Advances in Atmospheric Sciences》 2026年第1期259-262,共4页
Climate model prediction has been improved by enhancing model resolution as well as the implementation of sophisticated physical parameterization and refinement of data assimilation systems[section 6.1 in Wang et al.(... Climate model prediction has been improved by enhancing model resolution as well as the implementation of sophisticated physical parameterization and refinement of data assimilation systems[section 6.1 in Wang et al.(2025)].In relation to seasonal forecasting and climate projection in the East Asian summer monsoon season,proper simulation of the seasonal migration of rain bands by models is a challenging and limiting factor[section 7.1 in Wang et al.(2025)]. 展开更多
关键词 enhancing model resolution refinement data assimilation systems section climate model climate projection higher horizontal resolution seasonal forecasting simulation seasonal migration rain bands model resolution
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A peridynamics modeling approach for pre-cracked rock cracking processes under impact by integrating Drucker-Prager plasticity model and efficient contact model
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作者 Jingzhi Tu Nengxiong Xu Gang Mei 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期179-195,共17页
In rock engineering,natural cracks in rock masses subjected to external loads tend to initiate and propagate,leading to potential safety hazards.To investigate the effect of cracking behavior on the mechanical propert... In rock engineering,natural cracks in rock masses subjected to external loads tend to initiate and propagate,leading to potential safety hazards.To investigate the effect of cracking behavior on the mechanical properties of rocks,the cracking processes of pre-cracked rocks have been extensively studied using numerical modeling methods.The peridynamics(PD)exhibits advantages over other numerical methods due to the absence of the requirements for remeshing and external crack growth criterion.However,for modeling pre-cracked rock cracking processes under impact,current PD implementations lack generally applicable rock constitutive models and impact contact models,which leads to difficulties in determining rock material parameters and efficiently calculating impact loads.This paper proposes a non-ordinary state-based peridynamics(NOSBPD)modeling method integrating the Drucker-Prager(DP)plasticity model and an efficient contact model to address the above problems.In the proposed method,the Drucker-Prager plasticity model is integrated into the NOSBPD,thereby equipping NOSBPD with the capability to accurately characterize the nonlinear stress-strain relationship inherent in rocks.An efficient contact model between particles and meshes is designed to calculate the impact loads,which is essentially a coupling method of PD with the finite element method(FEM).The effectiveness of the proposed NOSBPD modeling method is verified by comparison with other numerical methods and experiments.Experimental results indicate that the proposed method can effectively and accurately predict the 3D cracking processes of pre-cracked cracks under impact loading,and the maximum principal stress is the key driver behind wing crack formation in pre-cracked rocks. 展开更多
关键词 Pre-cracked rocks Cracking processes Non-ordinary state-based peridynamics (NOSBPD) Drucker-Prager plasticity model Efficient contact model
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Secured-FL:Blockchain-Based Defense against Adversarial Attacks on Federated Learning Models
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作者 Bello Musa Yakubu Nor Shahida Mohd Jamail +1 位作者 Rabia Latif Seemab Latif 《Computers, Materials & Continua》 2026年第3期734-757,共24页
Federated Learning(FL)enables joint training over distributed devices without data exchange but is highly vulnerable to attacks by adversaries in the form of model poisoning and malicious update injection.This work pr... Federated Learning(FL)enables joint training over distributed devices without data exchange but is highly vulnerable to attacks by adversaries in the form of model poisoning and malicious update injection.This work proposes Secured-FL,a blockchain-based defensive framework that combines smart contract-based authentication,clustering-driven outlier elimination,and dynamic threshold adjustment to defend against adversarial attacks.The framework was implemented on a private Ethereum network with a Proof-of-Authority consensus algorithm to ensure tamper-resistant and auditable model updates.Large-scale simulation on the Cyber Data dataset,under up to 50%malicious client settings,demonstrates Secured-FL achieves 6%-12%higher accuracy,9%-15%lower latency,and approximately 14%less computational expense compared to the PPSS benchmark framework.Additional tests,including confusion matrices,ROC and Precision-Recall curves,and ablation tests,confirm the interpretability and robustness of the defense.Tests for scalability also show consistent performance up to 500 clients,affirming appropriateness to reasonably large deployments.These results make Secured-FL a feasible,adversarially resilient FL paradigm with promising potential for application in smart cities,medicine,and other mission-critical IoT deployments. 展开更多
关键词 Federated learning(FL) blockchain FL based privacy model defense FL model security ethereum smart contract
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Three-Dimensional Hybrid Model for Wave Interaction with Porous Layer
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作者 Divya Ramesh Sriram Venkatachalam 《Computer Modeling in Engineering & Sciences》 2026年第1期577-603,共27页
A hybrid model combining Fully Non-Linear Potential Flow Theory(FNPT)based on the Finite Element Method(FEM)and the Unified Navier-Stokes equation,using the 3D Improved Meshless Local Petrov Galerkin method with Ranki... A hybrid model combining Fully Non-Linear Potential Flow Theory(FNPT)based on the Finite Element Method(FEM)and the Unified Navier-Stokes equation,using the 3D Improved Meshless Local Petrov Galerkin method with Rankine Source(IMLPG_R),is developed to study wave interactions with a porous layer.In previous studies,the above formulations are applied to wave interaction with fixed cylindrical structures.The present study extends this framework by integrating a unified governing equation within the hybrid modeling approach to capture the dynamics of wave interaction with porous media.The porous layers are employed to replicate the wave-dissipating behavior of the structure.A weak coupling strategy is implemented within a designated buffer zone,wherein field variables from the 2D Fully Nonlinear Potential Theory(FNPT)simulations are transferred to the 3D Improved Moving Least Squares-based Petrov-Galerkin(IMLPG_R)model at each time step.This domain decomposition significantly reduces computational cost compared to a full 3D simulation by partitioning the domain into two subregions:the FNPT domain representing the far-field without structures,and the IMLPG_R domain encompassing the porous region.The Unified Navier-Stokes formulation is extended by incorporating additional drag forces governed by Darcy’s law to model the resistance introduced by the porous medium.A stationary background node framework is utilized for interpolation by fluid particles at each time step to accommodate the porous representation.To enhance numerical stability and accuracy,particularly in the presence of sloping boundaries,the Particle Shifting Technique(PST)is integrated into the IMLPG_R model.This implementation involves a modified version of the PST algorithm,where key parameters such as the weight function,velocity ratio,and radius of influence are optimized for IMLPG_R.This is the first time the application of 3D IMLPG_R for porous structure has been reported.Further,the model is subsequently validated against experimental data. 展开更多
关键词 FNPT IMLPG_R hybrid model PST
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A Predictive Model for the Elastic Modulus of High-Strength Concrete Based on Coarse Aggregate Characteristics
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作者 LI Liangshun LI Huajian +2 位作者 HUANG Fali YANG Zhiqiang DONG Haoliang 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期121-137,共17页
To investigate the influence of coarse aggregate parent rock properties on the elastic modulus of concrete,the mineralogical properties and stress-strain curves of granite and dolomite parent rocks,as well as the stre... To investigate the influence of coarse aggregate parent rock properties on the elastic modulus of concrete,the mineralogical properties and stress-strain curves of granite and dolomite parent rocks,as well as the strength and elastic modulus of mortar and concrete prepared with mechanism aggregates of the corresponding lithology,and the stress-strain curves of concrete were investigated.In this paper,a coarse aggregate and mortar matrix bonding assumption is proposed,and a prediction model for the elastic modulus of mortar is established by considering the lithology of the mechanism sand and the slurry components.An equivalent coarse aggregate elastic modulus model was established by considering factors such as coarse aggregate particle size,volume fraction,and mortar thickness between coarse aggregates.Based on the elastic modulus of the equivalent coarse aggregate and the remaining mortar,a prediction model for the elastic modulus of the two and three components of concrete in series and then in parallel was established,and the predicted values differed from the measured values within 10%.It is proposed that the coarse aggregate elastic modulus in highstrength concrete is the most critical factor affecting the elastic modulus of concrete,and as the coarse aggregate elastic modulus increases by 27.7%,the concrete elastic modulus increases by 19.5%. 展开更多
关键词 elastic modulus prediction model MINERALOGICAL influence mechanism
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Establishment of a mouse model of TMAO-induced cardiac injury and application of MICT intervention
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作者 Zhongping Xie Hong Zou +2 位作者 Lijing Gong Minghui Lin Caihua Huang 《Animal Models and Experimental Medicine》 2026年第1期142-153,共12页
Background:This study aims to explore the establishment of an animal model of car-diac injury induced by trimethylamine-N-oxide(TMAO),a metabolite secreted by gut microorganisms,and to investigate its application in m... Background:This study aims to explore the establishment of an animal model of car-diac injury induced by trimethylamine-N-oxide(TMAO),a metabolite secreted by gut microorganisms,and to investigate its application in moderate-intensity continuous training(MICT)intervention.Methods:C57BL6/J mice were randomly divided into four groups:normal mice(Nor,n=15);mice administered TMAO(TMAO,n=15);mice undergoing(Nor+MICT,n=15);mice undergoing(MICT)and administered TMAO(TMAO+MICT,n=15).Mice in the TMAO and TMAO+MICT groups received daily gavage of high-dose TMAO for 8 weeks,whereas those in the Nor+MICT and TMAO+MICT groups underwent MICT for 8 weeks(60 min per session,5 days per week,at 50%maximal running capacity).Cardiac function was evaluated using ultrasound,myocardial histology was examined using hematoxylin and eosin(HE)staining,and nuclear magnetic resonance(NMR)-based metabolomics was employed for multivariate statistical and metabolic pathway analyses.Results:Relative to the Nor group,TMAO-treated mice exhibited significant weight loss,elevated heart rate,and reduced ejection fraction and left ventricular fractional shortening,indicating cardiac impairment.Importantly,the TMAO+MICT group dem-onstrated significant improvements in these parameters compared to the TMAO group,alongside distinct alterations in myocardial metabolic profiles.TMAO altered five metabolic pathways relative to controls,whereas MICT induced significant changes in three pathways in TMAO-treated mice.Conclusion:Eight weeks of high-dose TMAO administration induced significant cardiac dysfunction in mice,which was effectively mitigated by MICT intervention.Consequently,this animal model serves as a valuable tool for investigating the mecha-nisms underlying the impact of MICT on cardiovascular diseases. 展开更多
关键词 animal model of injury HEART MICT TMAO
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