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Gray relational analysis and SBOA-BP for predicting settlement intervals of high-speed railway subgrade
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作者 Quanpeng He Shaoyuan Li 《Railway Sciences》 2025年第2期199-212,共14页
Purpose–The deformation of the roadbed is easily influenced by the external environment to improve the accuracy of high-speed railway subgrade settlement prediction.Design/methodology/approach–A high-speed railway s... Purpose–The deformation of the roadbed is easily influenced by the external environment to improve the accuracy of high-speed railway subgrade settlement prediction.Design/methodology/approach–A high-speed railway subgrade settlement interval prediction method using the secretary bird optimization(SBOA)algorithm to optimize the BP neural network under the premise of gray relational analysis is proposed.Findings–Using the SBOA algorithm to optimize the BP neural network,the optimal weights and thresholds are obtained,and the best parameter prediction model is combined.The data were collected from the sensors deployed through the subgrade settlement monitoring system,and the gray relational analysis is used to verify that all four influencing factors had a great correlation to the subgrade settlement,and the collected data are verified using the model.Originality/value–The experimental results show that the SBOA-BP model has higher prediction accuracy than the BP model,and the SBOA-BP model has a wider range of prediction intervals for a given confidence level,which can provide higher guiding value for practical engineering applications. 展开更多
关键词 Gray relational analysis Secretary bird optimization algorithm Backpropagation neural network Subgrade settlement Interval prediction
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Efficient Identification Method of Interbeds Based on Neural Network Combined with Grey Relational Analysis—Taking the Lower Sub-Member of the Sangonghe Formation in Moxizhuang Oilfield as an Example
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作者 Yuanbo Song Yankai Zhu Binxin Zeng 《Journal of Geoscience and Environment Protection》 2025年第2期51-68,共18页
The storage layer within the Moxizhuang Oilfield in the Junggar Basin develops various types of interlayer barriers with significant differences in morphology and scale of development. In response to the issues of int... The storage layer within the Moxizhuang Oilfield in the Junggar Basin develops various types of interlayer barriers with significant differences in morphology and scale of development. In response to the issues of interlayer barriers affecting the formation of oil and gas reservoirs and controlling oil-water distribution, this study proposes precise classification and quantitative identification of interlayer barriers in the study area based on a fully connected neural network combined with grey relational analysis. Taking the second member of the Sangonghe Formation (J1S22) in the Moxizhuang Oilfield as an example, combined with previous research, this study statistically analyzes the lithology and logging response characteristics of three types of interlayer barriers in the study area. Based on differences in composition, lithology, and genesis, interlayer barrier types are classified. Sensitive logging data such as natural gamma, acoustic time difference, and resistivity are selected through crossover plots. Grey relational analysis is used to calculate comprehensive discrimination indicators for interlayer barriers. Combined with the fully connected neural network method, an interlayer barrier identification model is established, and model training is conducted to verify the accuracy of interlayer barrier identification. The results indicate that the interlayer barrier identification model based on a fully connected neural network can rapidly and accurately identify interlayer barriers and their types. Its application in the second member of the Sangonghe Formation in the Moxizhuang Oilfield in the Junggar Basin has proven that the identification results of this method for interlayer barriers have a conformity rate exceeding 90% with core data, demonstrating excellent performance in interlayer barrier identification and proving the effectiveness of the model for interlayer barrier identification and prediction in this area. The research conclusions can provide theoretical guidance and technical reference for the identification and evaluation of interlayer barriers in the second member of the Sangonghe Formation in the Moxizhuang Oilfield in the Junggar Basin. 展开更多
关键词 Interlayer Recognition Grey Relational analysis Fully Connected Neural Network Second Member of Sangonghe Formation
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Link-16 anti-jamming performance evaluation based on grey relational analysis and cloud model
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作者 NING Xiaoyan WANG Ying +1 位作者 WANG Zhenduo SUN Zhiguo 《Journal of Systems Engineering and Electronics》 2025年第1期62-72,共11页
Anti-jamming performance evaluation has recently received significant attention. For Link-16, the anti-jamming performance evaluation and selection of the optimal anti-jamming technologies are urgent problems to be so... Anti-jamming performance evaluation has recently received significant attention. For Link-16, the anti-jamming performance evaluation and selection of the optimal anti-jamming technologies are urgent problems to be solved. A comprehensive evaluation method is proposed, which combines grey relational analysis (GRA) and cloud model, to evaluate the anti-jamming performances of Link-16. Firstly, on the basis of establishing the anti-jamming performance evaluation indicator system of Link-16, the linear combination of analytic hierarchy process(AHP) and entropy weight method (EWM) are used to calculate the combined weight. Secondly, the qualitative and quantitative concept transformation model, i.e., the cloud model, is introduced to evaluate the anti-jamming abilities of Link-16 under each jamming scheme. In addition, GRA calculates the correlation degree between evaluation indicators and the anti-jamming performance of Link-16, and assesses the best anti-jamming technology. Finally, simulation results prove that the proposed evaluation model can achieve the objective of feasible and practical evaluation, which opens up a novel way for the research of anti-jamming performance evaluations of Link-16. 展开更多
关键词 LINK-16 ANTI-JAMMING grey relational analysis(GRA) cloud model combination weights
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Construction of a value assessment framework for antineoplastic agents based on multi-criteria decision analysis in the context of diagnosis related group
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作者 Na Li Wu Fu +5 位作者 Jianying Lei Jiahao Zhang Caicong You Jingwen Lin Bin Zheng Maobai Liua 《Pharmacoeconomics and Policy》 2025年第1期42-50,共9页
This study aims to build a value assessment framework applicable to Chinese health-care institutions for antineoplastic agents in the context of diagnosis related group(DRG).This study constructed the value assessment... This study aims to build a value assessment framework applicable to Chinese health-care institutions for antineoplastic agents in the context of diagnosis related group(DRG).This study constructed the value assessment framework through literature research,Delphi expert consultation method,and analytic hierarchy process(AHP).This study used internal consistency reliability to test the reliability of the constructed framework.Exploratory factor analysis(EFA)and validation factor analysis were used for the validity test.Then,the level stratification of the indicators was set based on the literature data,and the value function of each indicator was constructed using the measuring attractiveness by a categorical based assessment technique method to construct a quantitative value assessment model.This study established a value assessment framework of 7 dimensions and 26 indicators.Reliability and validity analyses of these indicators made 4 indicators excluded.Then,the value functions were constructed for 17 indicators,establishing a quantitative value assessment model.This study constructed an antineoplastic drugs evaluation framework in the context of DRG with good validity and reliability and the corresponding quantitative value assessment model. 展开更多
关键词 Diagnosis related group Value assessment framework Multi-criteria decision analysis Antineoplastic agents
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A Hybrid Optimization Approach of Single Point Incremental Sheet Forming of AISI 316L Stainless Steel Using Grey Relation Analysis Coupled with Principal Component Analysiss
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作者 A Visagan P Ganesh 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期160-166,共7页
We investigated the parametric optimization on incremental sheet forming of stainless steel using Grey Relational Analysis(GRA) coupled with Principal Component Analysis(PCA). AISI 316L stainless steel sheets were use... We investigated the parametric optimization on incremental sheet forming of stainless steel using Grey Relational Analysis(GRA) coupled with Principal Component Analysis(PCA). AISI 316L stainless steel sheets were used to develop double wall angle pyramid with aid of tungsten carbide tool. GRA coupled with PCA was used to plan the experiment conditions. Control factors such as Tool Diameter(TD), Step Depth(SD), Bottom Wall Angle(BWA), Feed Rate(FR) and Spindle Speed(SS) on Top Wall Angle(TWA) and Top Wall Angle Surface Roughness(TWASR) have been studied. Wall angle increases with increasing tool diameter due to large contact area between tool and workpiece. As the step depth, feed rate and spindle speed increase,TWASR decreases with increasing tool diameter. As the step depth increasing, the hydrostatic stress is raised causing severe cracks in the deformed surface. Hence it was concluded that the proposed hybrid method was suitable for optimizing the factors and response. 展开更多
关键词 single point incremental forming AISI 316L taguchi grey relation analysis principal component analysis surface roughness scanning electron microscopy
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Optimization of short-circuit transition parameters of Q235B steel GMAW based on orthogonal gray relational analysis
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作者 陈昌荣 唐宝林 +2 位作者 叶宇杰 练国富 黄旭 《China Welding》 CAS 2024年第2期39-49,共11页
In gas metal arc welding(GMAW)process,the short-circuit transition was the most typical transition observed in molten metal droplets.This paper used orthogonal tests to explore the coupling effect law of welding proce... In gas metal arc welding(GMAW)process,the short-circuit transition was the most typical transition observed in molten metal droplets.This paper used orthogonal tests to explore the coupling effect law of welding process parameters on the quality of weld forming under short-circuit transition,the design of 3 factors and 3 levels of a total of 9 groups of orthogonal tests,welding current,welding voltage,welding speed as input parameters:effective area ratio,humps,actual linear power density,aspect ratio,Vickers hardness as output paramet-ers(response targets).Using range analysis and trend charts,we can visually depict the relationship between input parameters and a single output parameter,ultimately determining the optimal process parameters that impact the single output index.Then combined with gray the-ory to transform the three response targets into a single gray relational grade(GRG)for analysis,the optimal combination of the weld mor-phology parameters as follows:welding current 100 A,welding voltage 25 V,welding speed 30 cm/min.Finally,validation experiments were conducted,and the results showed that the error between the gray relational grade and the predicted value was 2.74%.It was observed that the effective area ratio of the response target significantly improved,validating the reliability of the orthogonal gray relational method. 展开更多
关键词 short-circuit transition orthogonal test gray relational forming quality
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Isogeometric Analysis of Hyperelastic Material Characteristics for Calcified Aortic Valve
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作者 Long Chen Ting Li +3 位作者 Liang Liu Wenshuo Wang Xiaoxiao Du Wei Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2773-2806,共34页
This study explores the implementation of computed tomography(CT)reconstruction and simulation techniques for patient-specific valves,aiming to dissect the mechanical attributes of calcified valves within transcathete... This study explores the implementation of computed tomography(CT)reconstruction and simulation techniques for patient-specific valves,aiming to dissect the mechanical attributes of calcified valves within transcatheter heart valve replacement(TAVR)procedures.In order to facilitate this exploration,it derives pertinent formulas for 3D multi-material isogeometric hyperelastic analysis based on Hounsfield unit(HU)values,thereby unlocking foundational capabilities for isogeometric analysis in calcified aortic valves.A series of uniaxial and biaxial tensile tests is executed to obtain an accurate constitutive model for calcified active valves.To mitigate discretization errors,methodologies for reconstructing volumetric parametric models,integrating both geometric and material attributes,are introduced.Applying these analytical formulas,constitutive models,and precise analytical models to isogeometric analyses of calcified valves,the research ascertains their close alignment with experimental results through the close fit in displacement-stress curves,compellingly validating the accuracy and reliability of the method.This study presents a step-by-step approach to analyzing themechanical characteristics of patient-specific valves obtained fromCT images,holding significant clinical implications and assisting in the selection of treatment strategies and surgical intervention approaches in TAVR procedures. 展开更多
关键词 Calcified aortic valves tensile test constitutive relations CT reconstruction isogeometric hyperelastic analysis
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Application of Critical Discourse Analysis in Post-Colonial Literary Studies
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作者 Yijing Chen 《Open Journal of Applied Sciences》 2024年第11期3183-3191,共9页
Post-colonial literary studies, as a significant academic field, have recently garnered widespread attention from scholars due to their integration with critical discourse analysis. This study explores the application... Post-colonial literary studies, as a significant academic field, have recently garnered widespread attention from scholars due to their integration with critical discourse analysis. This study explores the application of critical discourse analysis in post-colonial literary research, focusing on how this method reveals implicit power relations, identity construction, and cultural conflicts within texts. Through in-depth analysis of representative works, this study demonstrates how critical discourse analysis provides new perspectives and methodological tools for post-colonial literary studies. The research finds that critical discourse analysis can effectively deconstruct colonial discourse in texts, reveal authors’ ideological positions, and offer profound insights into understanding the complexity of post-colonial societies. This study not only enriches the methodology of post-colonial literary research, but also provides valuable references for interdisciplinary studies. 展开更多
关键词 Critical Discourse analysis Post-Colonial Literature Power Relations Identity Construction Interdisciplinary Research
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Cancer survival analysis on population-based cancer registry data in Zhejiang Province,China(2018-2019)
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作者 Huizhang Li Youqing Wang +5 位作者 Weiwei Gong Chen Zhu Le Wang Yaoyao Chen Lingbin Du Xiangdong Cheng 《Journal of the National Cancer Center》 2024年第1期54-62,共9页
Objective:This is a comprehensive overview of long-term cancer survival in Zhejiang Province,China.Hybrid analysis,a combination of cohort and period analysis,has been proposed to derive up-to-date cancer survival est... Objective:This is a comprehensive overview of long-term cancer survival in Zhejiang Province,China.Hybrid analysis,a combination of cohort and period analysis,has been proposed to derive up-to-date cancer survival estimates.Using this approach,we aimed to timely and accurately analyze the 5-year relative survival(RS)and net survival(NS)in cancer registries of Zhejiang Province,China.Methods:A total of 255,725 new cancer cases diagnosed during 2013-2017 were included in 14 cancer registries in Zhejiang Province,China,with a follow-up on vital status until the end of 2019.The hybrid analysis was used to calculate the 5-year RS and 5-year NS during 2018-2019 for overall and stratifications by sex,cancer type,region,and age at diagnosis.Results:During 2018-2019,the age-standardized 5-year RS and NS for overall cancer in Zhejiang was 47.5%and 48.6%,respectively.The age-standardized 5-year RS for cancers of women(55.4%)was higher than that of men(40.0%),and the rate of urban areas(49.7%)was higher than that of rural areas(43.1%).The 5-year RS declined along with age,from 84.4%for ages<45 years to 23.7%for ages>74 years.Our results of the RS and NS showed the similar trend and no significant difference.The top five cancers with top age-standardized 5-year RS were thyroid cancer(96.0%),breast cancer(84.3%),testicular cancer(79.9%),prostate cancer(77.2%),and bladder cancer(70.6%),and the five cancers with the lowest age-standardized 5-year RS were pancreatic cancer(6.0%),liver cancer(15.6%),gallbladder cancer(17.1%),esophageal cancer(22.7%),and leukemia(31.0%).Conclusions:We reported the most up-to-date 5-year cancer RS and NS in Zhejiang Province,China for the first time,and found that the 5-year survival for cancer patients in Zhejiang during 2018-2019 was relatively high.The population-based cancer registries are recognized as key policy tools that can be used to evaluate both the impact of cancer prevention strategies and the effectiveness of health systems. 展开更多
关键词 Cancer registry Cancer survival Hybrid analysis Relative survival Net survival
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Confirmatory analysis of the 13‐MD and ranking of its meta‐dimensions and items
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作者 Moustapha Touré Thomas G.Poder 《Health Care Science》 2024年第4期249-263,共15页
Background:The 13‐MD is a new generic instrument developed to measure general health‐related quality of life(GHRQoL).This instrument considers all aspects of health(i.e.,physical,mental,and social)in a balanced way.... Background:The 13‐MD is a new generic instrument developed to measure general health‐related quality of life(GHRQoL).This instrument considers all aspects of health(i.e.,physical,mental,and social)in a balanced way.A previous study led to minor changes in the original version of the 13‐MD.The objective of this study was to confirm the validity of the modified 13‐MD.Methods:Validity was assessed with recent data from the general population of Quebec,Canada.The meta‐dimensions and items composing the 13‐MD were also subjected to a ranking procedure,which allowed to determine the most important aspects for respondents.Results:A total of 1337 French‐speaking participants were recruited with 1099 completing the 13‐MD for validation purposes and 1084 completing the ranking procedure.The 13‐MD showed very satisfactory results and confirmed to be a valid instrument.The ranking of the meta‐dimensions revealed that“Well‐being”received the most points,followed by“Sleep and energy”and“Body functioning.”Conclusion:These results will be very useful in the continuous improvement of the 13‐MD,ultimately leading to the valuation stage(i.e.,development of a value set). 展开更多
关键词 cost‐utility analysis health‐related quality of life generic instrument
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甜瓜果实糖分代谢及相关酶活性分析
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作者 孔维萍 张凯莉 +4 位作者 唐桃霞 任凯丽 程鸿 魏虎霞 岳宏忠 《甘肃农业大学学报》 北大核心 2025年第1期105-111,共7页
【目的】研究不同糖分甜瓜果实糖分代谢与相关酶活性的关系,为甜瓜育种奠定基础。【方法】以高糖甜瓜日本甜宝和低糖甜瓜小翠瓜为试验材料,采用Elsa试剂盒测定甜瓜果实蔗糖、葡萄糖、果糖含量及代谢相关酶活性。【结果】不同发育时期甜... 【目的】研究不同糖分甜瓜果实糖分代谢与相关酶活性的关系,为甜瓜育种奠定基础。【方法】以高糖甜瓜日本甜宝和低糖甜瓜小翠瓜为试验材料,采用Elsa试剂盒测定甜瓜果实蔗糖、葡萄糖、果糖含量及代谢相关酶活性。【结果】不同发育时期甜瓜果实中葡萄糖和果糖含量变化不大,果糖含量略大于葡萄糖。日本甜宝果实中蔗糖含量整体呈上升趋势,小翠瓜果实在整个生长期基本无蔗糖积累。日本甜宝果实中蔗糖磷酸合成酶(Sucrose phosphate synthase,SPS)活性总体呈上升趋势,酸性转化酶(Acid invertase,AI)活性呈下降趋势;小翠瓜果实SPS与AI活性一直处于较低水平,变化幅度不大。日本甜宝果实蔗糖含量与SPS呈极显著正相关,相关系数达0.940,与AI呈负相关,相关系数为-0.31;小翠瓜果实蔗糖含量与SPS、AI均呈正相关且未达到显著水平,同时日本甜宝蔗糖含量与代谢相关酶均具有较高的正相关性,相关系数达到0.922,而小翠瓜果实蔗糖含量与代谢相关酶的相关性不显著,相关系数为0.683。【结论】通过对2个品种甜瓜果实蔗糖含量与相关酶活性相关性分析,果实糖分含量与蔗糖代谢酶净活性相关性分析,结果表明甜瓜果实中蔗糖含量与相关酶活性有着较高的相关性,且SPS在甜瓜蔗糖积累过程中发挥着重要作用,同时甜瓜果实中蔗糖的积累是受SPS、AI、中性转化酶(Neutral invertase,NI)、蔗糖合成酶(SS-S)以及蔗糖分解酶(SS-C)共同作用的结果。 展开更多
关键词 甜瓜 糖分积累 蔗糖代谢相关酶 相关性分析
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慢性肾脏病患者居家运动康复促进因素与障碍因素的质性研究
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作者 王微平 马迎春 《中国康复理论与实践》 北大核心 2025年第2期235-241,共7页
目的调查慢性肾脏病患者居家运动康复促进因素和障碍因素。方法2023年12月至2024年3月,选择曾就诊于北京博爱医院肾内科后居家的15例慢性肾脏病患者和肾内科的8例医护人员,进行半结构化访谈。采用Nvivo 12.0软件和主题分析法对访谈资料... 目的调查慢性肾脏病患者居家运动康复促进因素和障碍因素。方法2023年12月至2024年3月,选择曾就诊于北京博爱医院肾内科后居家的15例慢性肾脏病患者和肾内科的8例医护人员,进行半结构化访谈。采用Nvivo 12.0软件和主题分析法对访谈资料进行编码,并提炼主题。结果共提炼出2个主题:促进因素包括感知益处、良好的健康素养、互联网媒体潜在益处、医护人员的监督、充足的社会支持;障碍因素包括负面情绪严重、并发症的负面影响、重视程度不够、运动驱动力不足、运动时间场所等现实条件的约束、运动康复支持不足。结论慢性肾脏病患者居家运动康复影响因素多样并具有个性化,应个性化给予运动康复指导,提高患者自我管理依从性。 展开更多
关键词 慢性肾脏病 运动康复 相关因素 质性研究
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基于病案首页的神经外科住院绩效分析 被引量:1
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作者 杨林朋 《中国医药科学》 2025年第1期179-182,共4页
目的基于病案首页的神经外科疾病诊断相关组(DRG)住院绩效分析,结合神经外科医疗水平的核心指标,实现资源合理配置,提升医疗效率。方法抽取郑州大学第一附属医院2023年7月1日至12月31日出院的住院病案首页6217份,采用常规指标,利用DRG... 目的基于病案首页的神经外科疾病诊断相关组(DRG)住院绩效分析,结合神经外科医疗水平的核心指标,实现资源合理配置,提升医疗效率。方法抽取郑州大学第一附属医院2023年7月1日至12月31日出院的住院病案首页6217份,采用常规指标,利用DRG组数、相对权重(RW)、DRG总量、病例组合指数(CMI)、费用消耗指数、时间消耗指数、手术分级、病种结构等指标对2023年7月1日至12月31日神经系统疾病住院医疗服务绩效进行评价。结果神经外科出院人次6217人次,DRG总量12736.72,CMI值2.0487,DRG组数151组,费用指数1.01,时间指数0.99,RW≥2为3107人次,占比49.97%,手术人次4024人,手术人次占比64.73%,三、四级合计3118人,三、四级占比77.49%。结论神经外科主要以收治疑难重症为主,DRG住院绩效反映的结果科学、客观。 展开更多
关键词 疾病诊断相关组 神经外科 住院绩效 统计分析
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基于衰老视角的3种常见慢病共有机制与中药发现
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作者 崔春利 闫浩晨 +2 位作者 王敏 王川 孙继佳 《西安交通大学学报(医学版)》 北大核心 2025年第1期101-111,共11页
目的 通过生物信息学分析、机器学习算法和分子对接等方法和技术探讨非酒精性脂肪肝(NAFLD)、2型糖尿病(T2DM)和动脉粥样硬化(AS)3种常见慢病和衰老基因相关的共有机制和潜在治疗药物。方法 从AgingAtlas、CellAge、GenAge和MSigDB等数... 目的 通过生物信息学分析、机器学习算法和分子对接等方法和技术探讨非酒精性脂肪肝(NAFLD)、2型糖尿病(T2DM)和动脉粥样硬化(AS)3种常见慢病和衰老基因相关的共有机制和潜在治疗药物。方法 从AgingAtlas、CellAge、GenAge和MSigDB等数据库中收集和整理与衰老相关的基因。将从CTD、DisGeNET、GeneCards、OMIM、PharmGKB和TTD等数据库中获得与NAFLD、T2DM、AS相关的基因和基于GEO差异基因分析得到的基因集取交集后,得到这3种常见慢性疾病的相关疾病基因集。利用clusterProfiler包对衰老基因集、3种疾病相关基因集进行KEGG通路富集分析并取交集。将筛选得到的KEGG通路上的富集基因合并后,导入STRING数据库并构建PPI网络,利用MCODE工具分析得到PPI网络中的核心子模块,计算其中每个节点、模块的重要值Nim和Cim。同时,采用Lasso回归模型、Boruta算法以及随机森林模型等3种机器学习模型进行特征基因筛选。利用HIT2.0数据库查找关键特征基因相关的靶向中药小分子。利用SwissADME和ADMETlab 3.0在线系统对小分子进行ADMET评价和分析。利用分子对接方法对关键作用靶点和筛选到的小分子进行对接。结果 总共获得1 325、616、78、597个与衰老、NAFLD、T2DM、AS相关的基因。衰老和3种疾病的KEGG通路富集分析结果取交集后得到2条共有交集通路,共包含243个基因。构建PPI网络,3个核心子模块中Cluster 2的Cim值最高。根据特征基因筛选结果,结合PPI网络模块分析结果,找到4个与衰老相关的特征基因:CDK6、CDKN1A、MYC、PTEN。这4个靶点具有94个潜在中药小分子候选药物,其中,白藜芦醇(resveratrol, RSV)是这4个靶点共有的中药小分子。ADMET评价显示,其具有良好的成药性。PTEN靶点具有较高的Nim值,RSV与PTEN进行分子对接,显示有较好的结合稳定性。结论 从衰老的角度来看,发现了一种潜在的中药小分子RSV,它可能通过调节关键基因PTEN来预防和治疗NAFLD、T2DM和AS这3种常见的慢性疾病。 展开更多
关键词 衰老相关基因 生物信息学分析 老年慢性疾病 机器学习算法
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甜高粱茎秆含糖锤度时空变化规律研究
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作者 王官 张阳 +3 位作者 张伟 邵荣峰 常玉卉 赵威军 《中国农学通报》 2025年第2期28-35,共8页
本研究旨在解析甜高粱茎秆含糖锤度的变化规律,为甜高粱生物育种及生产实践提供理论依据。本研究以18份甜高粱品种为试验材料,通过方差分析、相关性分析、灰色关联度分析方法对不同时期茎秆含糖锤度、不同茎节含糖锤度、茎节与茎秆含糖... 本研究旨在解析甜高粱茎秆含糖锤度的变化规律,为甜高粱生物育种及生产实践提供理论依据。本研究以18份甜高粱品种为试验材料,通过方差分析、相关性分析、灰色关联度分析方法对不同时期茎秆含糖锤度、不同茎节含糖锤度、茎节与茎秆含糖锤度的关系进行分析。结果表明:甜高粱茎秆含糖锤度在时间维度上表现为S1、S2时期较低,S2-S3、S3-S4时期大幅增加,S4时期达到高峰;在垂直空间维度上表现为中部茎节含糖锤度最高,顶部、基部茎节含糖锤度较低,且不同茎节间含糖锤度随着茎节间垂直空间距离的增加正相关性逐渐变弱;另外不同茎节含糖锤度与茎秆含糖锤度关联次序为:基部茎节>中部茎节>顶部茎节,而中部茎节含糖锤度与茎秆含糖锤度数值最为接近。可见,在甜高粱生物育种过程中,中部茎节既可作为茎秆含糖锤度指示茎节,也是改良茎秆含糖锤度的突破口。 展开更多
关键词 甜高粱 含糖锤度 不同时期 不同茎节 方差分析 相关性分析 灰色关联度分析
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基于响应面法和灰色关联法的新型螺纹管传热性能优化研究
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作者 林纬 詹宏阳 +6 位作者 汪威 朱家豪 张鼎 龚程 郑小涛 徐建民 喻九阳 《武汉工程大学学报》 2025年第1期85-92,共8页
采用响应面法中的Box-Behnken法对新型螺纹管传热性能的优化进行实验设计,以努塞特数(Nu)和摩擦因数(f)为评价指标,研究螺距(P)、肋高(H)、螺纹段与光管段的长度比(L)对传热性能的影响,同时通过分析响应面图研究各参数对Nu和f的交互影... 采用响应面法中的Box-Behnken法对新型螺纹管传热性能的优化进行实验设计,以努塞特数(Nu)和摩擦因数(f)为评价指标,研究螺距(P)、肋高(H)、螺纹段与光管段的长度比(L)对传热性能的影响,同时通过分析响应面图研究各参数对Nu和f的交互影响。计算各实验组数的灰色关联等级,使用灰色关联法对新型螺纹管进行多目标优化,并通过分析不同换热管的湍流动能(TKE)分布,得到新型螺纹管增强传热性能的机理。研究表明:通过响应面分析可知L是影响Nu与f最显著的参数;通过灰色关联法分析得到的最优结构参数P=5.5 mm、H=1.00 mm、L=2,这种结构参数下的新型螺纹管Nu值为100.741,f值为0.024 641;通过对比不同换热管的TKE分布发现,新型螺纹管的独特设计即两个旋转方向相反的相邻螺纹段会导致管内的流体流动方向频繁变化,从而加剧径向扰动,更频繁地产生二次流,导致TKE增加,增强其传热性能。通过优化研究,确定了新型螺纹管最优的结构参数,并深入揭示其传热性能增强的机制,为进一步优化和设计新型螺纹管提供了指导和依据。 展开更多
关键词 螺纹管 灰色关联法 响应面法 强化传热
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平曲线要素对小客车运行碳排放的影响特征研究
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作者 王晓飞 罗振 +2 位作者 王少华 潘玲 曾强 《华南理工大学学报(自然科学版)》 北大核心 2025年第2期68-79,共12页
我国“十四五”发展规划对交通绿色发展提出了更高要求,交通运营所产生的排放是交通行业碳排放的主要来源。为研究公路平曲线路段小客车运行碳排放的影响因素,通过开展现场实车试验,试验车载OBD(On Board Diagnostics)设备采集广东省内... 我国“十四五”发展规划对交通绿色发展提出了更高要求,交通运营所产生的排放是交通行业碳排放的主要来源。为研究公路平曲线路段小客车运行碳排放的影响因素,通过开展现场实车试验,试验车载OBD(On Board Diagnostics)设备采集广东省内典型公路曲线段现场行车试验数据,并通过IPCC(Intergovernmental Panel on Climate Change)碳排放核算方法获取路段碳排放率数据,结合道路线形选取了影响小客车运行排放的相关评价指标,在灰色关联分析的基础上对相关评价指标进行关联度计算。结果表明:平曲线路段线形要素中缓和曲线长度占比、缓和曲线参数等指标与路段碳排放率显著关联;圆曲线半径在一定区间内与路段碳排放率显著关联。非线形指标中显著相关的有加速度标准差和加速度均值,与这两者显著相关的线形指标是缓和曲线参数和缓和曲线长度占比。结合灰色关联分析结果,从指标中选取了8个关联指标,通过建立灰色GM(1,N)模型对平曲线路段小客车行驶碳排放总量进行预测,预测结果和实际结果平均相对误差为5.10%,模型预测性能优于传统多元回归模型,在数据有限的情况下表现出色并提供可靠的预测结果。研究成果可识别路段对碳排放有显著影响的关键设计和运行参数,为平曲线路段低碳优化设计和管理提供理论依据。 展开更多
关键词 公路 平曲线 碳排放率 灰色关联度 小客车
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矿区野生苎麻对贫瘠及重金属污染土壤适应能力的比较研究
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作者 吴胜兰 揭红东 +1 位作者 邢虎成 揭雨成 《环境生态学》 2025年第2期110-117,共8页
通过对湖南省5个矿区20个观测样区生长的苎麻种质资源进行调研及分析,以期筛选获得一批适应重金属污染贫瘠土壤的种质。通过调研相应苎麻居群的表型性状,并采用灰色关联分析法对采集样品与已筛选出的优势种质进行比较;接着还对相应种质... 通过对湖南省5个矿区20个观测样区生长的苎麻种质资源进行调研及分析,以期筛选获得一批适应重金属污染贫瘠土壤的种质。通过调研相应苎麻居群的表型性状,并采用灰色关联分析法对采集样品与已筛选出的优势种质进行比较;接着还对相应种质的重金属富集能力进行了评价。重金属矿区瘠薄土壤生长的20份野生苎麻种质变异丰富(表型变异度最高达65.10%)、遗传多样性高(香农指数最高达2.02)。在土壤更为贫瘠且同时具有重金属胁迫的环境条件下,野生种质J3-4(来源于花垣矿区)与已筛选得到的贫瘠土壤适应性强的种质湘苎XB表型接近(灰色关联度为0.739)甚至地上生物产量更高。该种质对Pb和Cd的富集能力较强(转移系数均大于1),每平方米的地上生物质可吸收富集40.56 mg的Pb和4.37 mg的Cd。本研究筛选得到了一批贫瘠土壤适应性强及重金属耐受能力较强的种质,为苎麻在矿山复垦地和重金属污染地种植及相关育种工作提供材料支撑。 展开更多
关键词 苎麻 矿山修复 重金属污染 灰色关联度 资源评价
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稳定车作业下道床横向阻力在线检测模型研究
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作者 陈春俊 江浩 林梦 《铁道科学与工程学报》 北大核心 2025年第1期136-145,共10页
稳定车是一种大型轨道交通运维装备,通过稳定作业来提高有砟轨道的道床横向阻力,但是无法在线检测作业下的道床横向阻力。为探究稳定车作业下道床横向阻力的在线检测方法,在有砟轨道线路上开展现场试验,获取稳定作业参数及稳定装置横向... 稳定车是一种大型轨道交通运维装备,通过稳定作业来提高有砟轨道的道床横向阻力,但是无法在线检测作业下的道床横向阻力。为探究稳定车作业下道床横向阻力的在线检测方法,在有砟轨道线路上开展现场试验,获取稳定作业参数及稳定装置横向加速度的在线信号,作业前后离线检测道床横向阻力。采用与轨枕纵向间距等长度的空间窗截取在线信号,使得在线测试结果与作业后道床横向阻力离线测试结果相匹配。采用灰色关联度分析法评估稳定作业试验数据与作业后道床横向阻力的相关性,提取出稳定车作业下道床横向阻力的特征参数。根据试验数据集,确定RBF神经网络模型的结构,并采用PSO算法优化RBF神经网络模型的参数,进而对比PSO-RBF模型和RBF模型对于道床横向阻力的计算误差。结果表明:稳定车作业时,激振频率、走行速度、左下压力、右下压力、稳定装置横向加速度与作业后道床横向阻力之间的灰色关联度分别为0.68、0.64、0.70、0.70和0.71,在线特征参数可以反映出离线的道床横向阻力特性。在测试集验证中,相较于RBF模型,PSO-RBF模型的最大绝对误差降低54.12%,平均绝对误差降低47.30%,均方根误差降低44.21%,拟合优度由0.90提高到0.97,PSO算法的引入提高了道床横向阻力模型的计算精度。研究成果可为稳定车作业下道床横向阻力的在线检测提供理论依据,推进轨道交通运维技术的智能化发展。 展开更多
关键词 稳定车 道床横向阻力 RBF神经网络 粒子群优化 灰色关联度
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体外循环术后患者呼吸装置相关压力性损伤发生特征及影响因素
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作者 马琴 王志伟 +1 位作者 马晶 张莉 《临床荟萃》 2025年第3期231-236,共6页
目的探讨体外循环术后患者由呼吸装置造成的器械相关压力性损伤(medical device-related pressure injury,MDRPI)的发生特征,并分析其影响因素。方法采用便利抽样法选取2023年6月-2024年4月新疆医科大学第一附属医院心脏外科重症监护室... 目的探讨体外循环术后患者由呼吸装置造成的器械相关压力性损伤(medical device-related pressure injury,MDRPI)的发生特征,并分析其影响因素。方法采用便利抽样法选取2023年6月-2024年4月新疆医科大学第一附属医院心脏外科重症监护室体外循环术后患者426例。依据是否发生由呼吸装置导致的MDRPI分为MDRPI组(n=99)和非MDRPI组(n=327)。应用单因素分析及Lasso回归筛选影响因素并纳入logistic回归分析。结果426例患者中MDRPI 99例(22.2%)。Logistic回归分析显示:术中肝素钠用量较多、急诊手术、术后发热、体外循环时间较长均为独立危险因素(均OR>1,P<0.05),护士能级较高、血小板水平较高均为保护因素(OR<1,P<0.05)。所构建模型AUC=0.874(95%CI:0.837~0.910),敏感度0.828,特异度0.768,模型区分度较好;H-L检验(χ^(2)=3.094,P=0.928)模型拟合度较好。结论体外循环术后患者可因术中肝素钠用量较多、血小板水平较低、急诊手术、术后发热、体外循环时间较长及护士能级较低导致患者易并发MDRPI,临床护士应全面评估,给予预见性预防措施,从而降低其发生风险。 展开更多
关键词 体外循环 呼吸装置 器械相关压力性损伤 发生特征 影响因素分析
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