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Stress signaling caused by mitochondrial import malfunction can be terminated by SIFI:Importance of stress response silencing
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作者 Grace Hohman Michael Shahid Mohamed A.Eldeeb 《Neural Regeneration Research》 2026年第2期673-674,共2页
Protein aggregates,mitochondrial import stress and neurodegenerative disorders:A salient hallmark of several neurodegenerative diseases,including Parkinson’s disease,is the abundance of protein aggregates(Goiran et a... Protein aggregates,mitochondrial import stress and neurodegenerative disorders:A salient hallmark of several neurodegenerative diseases,including Parkinson’s disease,is the abundance of protein aggregates(Goiran et al.,2022).This molecular event is believed to lead to activation of stress pathways ultimately resulting in cellular dysfunction(Eldeeb et al.,2022).Accordingly,many lines of research investigations focused on dampening the formation of protein aggregates or augmenting the clearance of protein aggregates as a potential therapeutic strategy to counteract the progression of neurodegenerative diseases,albeit with little success(Costa-Mattioli and Walter,2020).Cell stress cues such as the accumulation of protein aggregates lead to the activation of stress response pathways that aid cells in responding to the damage.Despite the notion that the transient activation of these pathways helps cells cope with stressors,persistent activation can induce unwanted apoptosis of cells and reduce overall tissue strength as well as lead to an accumulation of aggregation-prone proteins(Hetz and Papa,2018).Mutations in proteins involved in stress signaling termination can cause conditions like ataxia and early-onset dementia(Conroy et al.,2014).Therefore,it is crucial for stress response signaling to be turned off once conditions have improved.Nevertheless,the mechanisms by which cells silence these signals are still elusive. 展开更多
关键词 activation stress pathways neurodegenerative disorders protein aggregatesmitochondrial import stress stress signaling protein aggregates goiran protein aggregates protein aggr neurodegenerative diseasesincluding
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基于Null Importance分析慢病人群接受居家药学服务意愿的影响因素
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作者 赵科 杨宏昕 +2 位作者 武明芬 郭浩 赵志刚 《医药导报》 北大核心 2025年第8期1347-1351,共5页
目的探究慢病人群接受居家药学服务意愿的关键影响因素。方法采用中国适老化研究项目中内蒙古自治区及东北地区的调查数据,基于Null Importance方法,筛选影响慢病人群参与居家药学服务意愿的关键因素。构建logistic回归模型,采用5折交... 目的探究慢病人群接受居家药学服务意愿的关键影响因素。方法采用中国适老化研究项目中内蒙古自治区及东北地区的调查数据,基于Null Importance方法,筛选影响慢病人群参与居家药学服务意愿的关键因素。构建logistic回归模型,采用5折交叉验证方法,以准确率及AUC为指标,评价特征选择对模型性能的影响。结果Null Importance方法筛选出10个关键因素,且特征选择后logistic回归模型性能得到提升。显著影响患者对居家药学服务接受意愿的因素包括:获取药品信息途径个数(OR=1.261,95%CI=1.182~1.345),药物适应证认知(OR=1.342,95%CI=1.124~1.603),是否保留药盒(OR=1.218,95%CI=1.015~1.462),用药依从性得分(OR=0.881,95%CI=0.839~0.925),用药素养得分(OR=0.631,95%CI=0.488~0.817),用药指导服务了解程度(OR=1.211,95%CI=1.017~1.442)。结论在Null Importance特征选择方法基础上构建的logistic回归模型,具有良好的性能,有助于慢病人群接受居家药学服务意愿影响因素的分析。 展开更多
关键词 Null importance 居家药学服务 意愿 慢病
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Distribution,species richness,and relative importance of different plant life forms across drylands in China 被引量:1
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作者 Shuran Yao Weigang Hu +16 位作者 Mingfei Ji Abraham Allan Degen Qiajun Du Muhammad Adnan Akram Yuan Sun Ying Sun Yan Deng Longwei Dong Haiyang Gong Qingqing Hou Shubin Xie Xiaoting Wang Jinzhi Ran Bernhard Schmid Qinfeng Guo Karl J.Niklas Jianming Deng 《Plant Diversity》 2025年第2期273-281,共9页
Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmen... Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmental gradients.Particularly,the relative importance(RIV)of different plant life forms in a community and how they vary with environmental variables are still unclear.To fill these gaps,we determined plant diversity of ephemeral plants,annual herbs,perennial herbs,and woody plants from 187 sites across drylands in China.The SR patterns of herbaceous plants,especially perennial herbs,and their RIV in plant communities increased with increasing precipitation and soil nutrient content;however,the RIV of annual herbs was not altered along these gradients.The SR and RIV of ephemeral plants were affected mainly by precipitation seasonality.The SR of woody plants had a unimodal relationship with air temperature and exhibited the highest RIV and SR percentage in plant communities under the harshest environments.An obvious shift emerged in plant community composition,SR and their critical impact factors at 238.5 mm of mean annual precipitation(MAP).In mesic regions(>238.5 mm),herbs were the dominant species,and the SR displayed a relatively slow decreasing rate with increasing aridity,which was mediated mainly by MAP and soil nutrients.In arid regions(<238.5 mm),woody plants were the dominant species,and the SR displayed a relatively fast decreasing rate with increasing aridity,which was mediated mainly by climate variables,especially precipitation.Our findings highlight the importance of comparative life form studies in community structure and biodiversity,as their responses to gradients differed substantially on a large scale. 展开更多
关键词 DRYLANDS Environmental gradients Plant life forms Relative importance Species richness THRESHOLD
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Analysis of Influencing Factors of Academic Warning in Higher Vocational Colleges Based on the Importance of Machine Learning Features and Paths to Improve Learning Ability 被引量:1
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作者 Meimei Huang Lei Zhang Xifeng Fan 《Journal of Contemporary Educational Research》 2025年第5期75-80,共6页
The traditional academic warning methods for students in higher vocational colleges are relatively backward,single,and have many influencing factors,which have a limited effect on improving their learning ability.A da... The traditional academic warning methods for students in higher vocational colleges are relatively backward,single,and have many influencing factors,which have a limited effect on improving their learning ability.A data set was established by collecting academic warning data of students in a certain university.The importance of the school,major,grade,and warning level for the students was analyzed using the Pearson correlation coefficient,random forest variable importance,and permutation importance.It was found that the characteristic of the major has a great impact on the academic warning level.Countermeasures such as dynamic adjustment of majors,reform of cognitive adaptation of courses,full-cycle academic support,and data-driven precise intervention were proposed to provide theoretical support and practical paths for universities to improve the efficiency of academic warning and enhance students’learning ability. 展开更多
关键词 Academic warning Pearson correlation coefficient Random forest variable importance Permutation importance
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Corrigendum to“Meta databases of steel frame buildings for surrogate modelling and machine learning-based feature importance analysis”[Journal of Resilient Cities and Structures Volume 3 Issue 1(2024)20-43]
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作者 Delbaz Samadian Jawad Fayaz +2 位作者 Imrose B.Muhit Annalisa Occhipinti Nashwan Dawood 《Resilient Cities and Structures》 2025年第1期124-124,共1页
The authors regret that the original publication of this paper did not include Jawad Fayaz as a co-author.After further discussions and a thorough review of the research contributions,it was agreed that his significan... The authors regret that the original publication of this paper did not include Jawad Fayaz as a co-author.After further discussions and a thorough review of the research contributions,it was agreed that his significant contributions to the foundational aspects of the research warranted recognition,and he has now been added as a co-author. 展开更多
关键词 machine learning meta databases jawad fayaz surrogate modelling feature importance analysis steel frame buildings
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Unveiling hidden biases in machine learning feature importance
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作者 Yoshiyasu Takefuji 《Journal of Energy Chemistry》 2025年第3期49-51,共3页
Nirmal et al.presented a machine learning-based design of ternary organic solar cells,utilizing feature importance[1].This paper highlights the alarming potential biases in the use of feature importance in machine lea... Nirmal et al.presented a machine learning-based design of ternary organic solar cells,utilizing feature importance[1].This paper highlights the alarming potential biases in the use of feature importance in machine learning,which can lead to incorrect conclusions and outcomes.Many scientists and researchers including Nirmal et al.are unaware that feature importances in machine learning in general are model-specific and do not necessarily represent true associations between the target and features. 展开更多
关键词 Machine learning Feature importance Potential bias Chi-squared and P-value
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Moderate Deviations for the Optimal Values of Sample Average Approximation with Adaptive Multiple Importance Sampling
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作者 Wenjin ZHANG 《Journal of Mathematical Research with Applications》 2025年第2期275-284,共10页
In this paper, we use sample average approximation with adaptive multiple importance sampling to explore moderate deviations for the optimal values. Utilizing the moderate deviation principle for martingale difference... In this paper, we use sample average approximation with adaptive multiple importance sampling to explore moderate deviations for the optimal values. Utilizing the moderate deviation principle for martingale differences and an appropriate Delta method, we establish a moderate deviation principle for the optimal value. Moreover, for a functional form of stochastic programming, we obtain a functional moderate deviation principle for its optimal value. 展开更多
关键词 adaptive multiple importance sampling martingale difference moderate deviation
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辽宁省输入性恶性疟原虫耐药性相关基因Pfcrt序列的多态性分析
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作者 王博 李鑫 +4 位作者 雷露 王周超 孙英伟 于维君 毛玲玲 《中国病原生物学杂志》 北大核心 2026年第1期1-5,12,共6页
目的本研究旨在检测恶性疟原虫(Plasmodium falciparum)氯喹抗性转运蛋白(Pfcrt)基因的多态性,分析其结构区域的序列变异,以期为掌握辽宁省恶性疟的耐药性情况进展和提供临床有效治疗方案提供科学的理论依据。方法收集了从2019-2021年... 目的本研究旨在检测恶性疟原虫(Plasmodium falciparum)氯喹抗性转运蛋白(Pfcrt)基因的多态性,分析其结构区域的序列变异,以期为掌握辽宁省恶性疟的耐药性情况进展和提供临床有效治疗方案提供科学的理论依据。方法收集了从2019-2021年期间的辽宁省输入性恶性疟疟疾病例患者的全血,采集了相关患者的流行病学信息。采用巢氏多重PCR的方法对恶性疟患者的全血样本进行Pfcrt耐药基因的扩增并且对其进行基因序列比对,对其目前输入性恶性疟原虫耐药基因的多态性进行详尽分析以及阐述其流行分布特征。本次共检测到18份病例患者的血样,扩增出的目的产物经测序获得到了Pfcrt基因序列,并在基因库中与恶性疟原虫的标准株3D7(PF3D7-265519)序列进行Blast比对分析,使用Mega5.05软件对其进行了序列多态性的分析,并计算出序列之间的有效变异位点,遗传距离和氨基酸突变位点构成比。结果本研究收集的辽宁省输入性恶性疟患者样本病例全部来自非洲,包括安哥拉、刚果布、刚果金、几内亚、尼日利亚、乌干达、喀麦隆。经过比对分析目前辽宁省恶性疟原虫Pfcrt基因存在着3种类型,即CVMNK型、CVIET型和CVMNT型。分析得出在突变型基因(CVIET)中的突变位点的发生主要在74、75、76位氨基酸,它的碱基突变分别为ATG→AAT、AAT→GAA和AAA→ACA,导致氨基酸的变化:M74I、N75E和K76T。这些突变类型与氯喹耐药性密切相关,尤其是K76T突变已被广泛认为是氯喹耐药性的重要标志。结论CVMNK型是最常见的Pfcrt基因类型,且氯喹敏感型仍占主导地位。研究结果提示,目前辽宁省氯喹依然可以作为恶性疟原虫有效的治疗选择。但CVIET型等突变型的存在也提示氯喹耐药性在部分地区可能逐渐发展,因此需要进一步加强对氯喹耐药性的监测和评估。尽管本文研究的样本较少,但结果为氯喹耐药性的分布和演变提供了有效信息,仍需范围内开展进一步的监测工作,以应对潜在的抗疟药物耐药性风险。 展开更多
关键词 输入性恶性疟 耐药性 基因 多态性分析 辽宁省
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Face tracking algorithm based on particle filter with mean shift importance sampling 被引量:2
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作者 高建坡 杨浩 +1 位作者 安国成 吴镇扬 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期196-201,共6页
The condensation tracking algorithm uses a prior transition probability as the proposal distribution, which does not make full use of the current observation. In order to overcome this shortcoming, a new face tracking... The condensation tracking algorithm uses a prior transition probability as the proposal distribution, which does not make full use of the current observation. In order to overcome this shortcoming, a new face tracking algorithm based on particle filter with mean shift importance sampling is proposed. First, the coarse location of the face target is attained by the efficient mean shift tracker, and then the result is used to construct the proposal distribution for particle propagation. Because the particles obtained with this method can cluster around the true state region, particle efficiency is improved greatly. The experimental results show that the performance of the proposed algorithm is better than that of the standard condensation tracking algorithm. 展开更多
关键词 face tracking particle filter importance sampling CONDENSATION mean shift
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Importance measure of system reliability upgrade for multi-state consecutive k-out-of-n systems 被引量:3
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作者 HonQvan Dui Shubin si +2 位作者 Zhiqiang Cai Shudong Sun Yingfeng Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第6期936-942,共7页
Importance measures in reliability systems are used to identify weak components in contributing to a proper function of the system.Traditional importance measures mainly concerned the changing value of the system reli... Importance measures in reliability systems are used to identify weak components in contributing to a proper function of the system.Traditional importance measures mainly concerned the changing value of the system reliability caused by the change of the reliability of the component,and seldom considered the joint effect of the probability distribution,improvement rate of the object component.This paper studies the rate of the system reliability upgrading with an improvement of the component reliability for the multi-state consecutive k-out-of-n system.To verify the multi-state consecutive k-out-of-n system reliability upgrading by improving one component based on its improvement rate,an increasing potential importance(IPI)and its physical meaning are described at first.Secondly,the relationship between the IPI and Birnbaum importance measures are discussed.And the IPI for some different improvement actions of the component is further discussed.Thirdly,the characteristics of the IPI are analyzed.Finally,an application to an oil pipeline system is given. 展开更多
关键词 system reliability multi-state consecutive k-out-of-nsystem IMPROVEMENT Birnbaum importance.
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迈向世界重要教育中心:来华留学的战略布局与实现路径
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作者 吕萍 刘进 于宜田 《高校教育管理》 北大核心 2026年第1期36-45,共10页
国际学生比例是衡量高等教育强国全球吸引力、结构质量与战略影响力的核心指标。基于全球主要高等教育中心国家的实践经验,国际学生比例的战略价值通过政策调控、分层布局与学科集聚三大路径实现。结合我国来华留学教育发展规律与高等... 国际学生比例是衡量高等教育强国全球吸引力、结构质量与战略影响力的核心指标。基于全球主要高等教育中心国家的实践经验,国际学生比例的战略价值通过政策调控、分层布局与学科集聚三大路径实现。结合我国来华留学教育发展规律与高等教育规模特征,构建保守、基准、跨越三重情景模拟,到2035年若要占据全球10%的国际学生市场份额,我国需吸引约105万国际学生,对应国际学生比例为1.71%,这一水平与教育强国综合实力相适配。为达成这一目标,我国在来华留学上要进行战略重心转移,构建以质量为核心的战略引力体系;优化培养结构,以硕博研究生为主体进行战略性资源配置;调整学科布局,服务国家硬实力与提升全球叙事能力;改革评价机制,建立与资源挂钩的“质量-贡献”反馈体系。 展开更多
关键词 国际学生比例 高等教育强国 来华留学 世界重要教育中心 质量提升 战略布局
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Thorium and Its Future Importance for Nuclear Energy Generation 被引量:1
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作者 Paulo E.O.Lainetti 《Journal of Energy and Power Engineering》 2016年第10期600-605,共6页
Thorium was discovered in 1828 by the Swedish chemist Jons J.Berzelius.Despite some advantages over uranium for use in nuclear reactors,its main use,in the almost two centuries since its discovery,thorium was restrict... Thorium was discovered in 1828 by the Swedish chemist Jons J.Berzelius.Despite some advantages over uranium for use in nuclear reactors,its main use,in the almost two centuries since its discovery,thorium was restricted to use for gas mantles,especially in the early 20th century.In the beginning of the nuclear era,many countries had interested on thorium,particularly during the 1950-1970 period.There are about 435 nuclear reactors in the world nowadays.They need more than 65,000 tons of uranium yearly.The future world energy needs will increase and,even if we assumed a conservative contribution of nuclear generation,there will be a significant increasing in the uranium prices occur,taking into account that uranium,as used in the present thermal reactors,is a finite resource.Thorium is nearly three times more abundant than uranium in the Earth's crust.Despite thorium is not a fissile material,^232Th can be converted to^233U(fissile)more efficiently than^238U to^239pu.Besides this,since it is possible to convert thorium waste into non-radioactive elements,thorium is an environment-friendly alternative energy source.Thorium fuel cycle is also inherently resistant to proliferation.Some papers evaluate the thorium resources in Brazil over 1,200,000 metric t.Then,the thorium alternative must be seriously considered in Brazil for strategic reasons.In this paper a brief history of thorium is presented,besides a review of the world thorium utilization and a discussion about advantages and restrictions of thorium use. 展开更多
关键词 NUCLEAR energy importance THORIUM Brazilian resources strategic importance.
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濒危植物夏蜡梅3种林型的群落特征比较
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作者 余臻 秦娇 +1 位作者 金则新 王晓燕 《森林与环境学报》 北大核心 2026年第1期82-90,共9页
为揭示夏蜡梅(Calycanthus chinensis)在不同植被类型生境中的适应性机制,以浙江省天台县夏蜡梅所处的3种典型林型[落叶常绿阔叶混交林(简称混交林)、杉木(Cunninghamia lanceolata)林和毛竹(Phyllostachys edulis)林]的植物群落为研究... 为揭示夏蜡梅(Calycanthus chinensis)在不同植被类型生境中的适应性机制,以浙江省天台县夏蜡梅所处的3种典型林型[落叶常绿阔叶混交林(简称混交林)、杉木(Cunninghamia lanceolata)林和毛竹(Phyllostachys edulis)林]的植物群落为研究对象,用样方法调查乔木层、灌木层和草本层植物,分析群落物种组成、多样性及林分结构特征。结果表明:3种林型共有维管植物231种,物种丰富度为混交林>毛竹林>杉木林,各林型间物种组成存在极显著差异(P=0.001);林分结构显示,混交林与杉木林木本植物密度随径级和树高增加呈近“J”形分布,毛竹林呈近倒“J”形分布,夏蜡梅则为间歇(多峰)型;乔木层Shannon-Wiener指数与Pielou指数表现为混交林>杉木林>毛竹林;混交林乔灌层有多个多样性指数与夏蜡梅生长指标呈显著及以上的正相关关系(P<0.05),而毛竹个体数则与夏蜡梅生长呈显著(0.01≤P<0.05)或极显著(P<0.001)负相关。建议优先选择混交林和毛竹林作为夏蜡梅种群恢复的核心生境,并通过调控前者乔灌层多样性,同时对后者适度疏伐,以实现科学抚育。 展开更多
关键词 夏蜡梅 植物群落 林分结构 重要值 Α多样性 群落结构
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Attaching Importance to the Strategy of Mathematical Culture in College Mathematics Teaching
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作者 Xiaohong Zhou Changrui Deng 《International Journal of Technology Management》 2017年第6期80-83,共4页
The modem times industrial technology and the mathematics mutual promotion, the new technological revolution origins from thecomputation technology improvement, the modem network world is closely linked with the mathe... The modem times industrial technology and the mathematics mutual promotion, the new technological revolution origins from thecomputation technology improvement, the modem network world is closely linked with the mathematics, mathematics development promotedthe technology advancement, the technology advancement also to impetus basic mathematics development, the two promoted the human culturedevelopment together, has brought the modem culture and the civilized unprecedented prosperity, also widely was affecting the modem life andthe thought. This paper analyzed the idea of attaching the importance to the strategy of mathematical culture in the college mathematics teaching.The proposed method is of great importance of enhancing the further direction of the mathematical education paradigms. 展开更多
关键词 MATHEMATICAL Culture MATHEMATICS Teaching Attaching importance.
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Dandyism in Oscar Wilde's The Importance of Being Earnest
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作者 宫昀 《海外英语》 2017年第11期166-168,共3页
In The Importance of Being Earnest,Oscar Wilde constructs a dandies’world,in which the persons mock at everything and subvert everything.This research analyzes the dandyish features of the character with the aid of C... In The Importance of Being Earnest,Oscar Wilde constructs a dandies’world,in which the persons mock at everything and subvert everything.This research analyzes the dandyish features of the character with the aid of Charles Baudelaire’s definition of dandy and dandyism,and studies Wilde’s subversion of the preexistent binary oppositions by referring to Jonathan Culler’s interpretation of Jacque Derrida’s deconstruction,and points out that Wilde’s writing in Earnest is a deconstructionist writing.He abandons all the so-called essential matters and only focuses on linguistic surface and comic effect.His stance of dandyism challenges the main-stream social norms at his time and foresees the coming artistic trend. 展开更多
关键词 dandyism SUBVERSION The importance of Being Earnest
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基于Kano模型的训练伤康复护理需求分析与干预策略优化
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作者 陈娟 李春月 +4 位作者 赖晓荣 文彩虹 朱欣娟 程晶晶 何瑛 《中国疗养医学》 2026年第1期67-73,共7页
目的了解训练伤患者康复护理需求的属性并进行优化排序,探究影响因素,为制定针对性的优化策略提供理论依据。方法采用便利抽样法抽取333名训练伤康复患者,基于Kano模型设计问卷并进行调查,分析训练伤康复患者护理需求的Kano属性,通过重... 目的了解训练伤患者康复护理需求的属性并进行优化排序,探究影响因素,为制定针对性的优化策略提供理论依据。方法采用便利抽样法抽取333名训练伤康复患者,基于Kano模型设计问卷并进行调查,分析训练伤康复患者护理需求的Kano属性,通过重要性和满意度调查,进行重要性-满意度(IPA)矩阵分析,确定患者需求改进的优先序。结果单因素分析显示,训练伤患者的性别、年龄、文化程度、病程、家庭收入对满意度的影响有高度统计学意义(P<0.01)。根据Kano属性分类,10个条目中9个属于期望型,1个属于魅力型;各需求满意度均分4.024~4.625,重要性均分4.393~4.679;IPA矩阵图显示,5项服务位于第1象限,3项服务位于第2象限,2项服务位于第3象限。分析发现家人/朋友参与和疼痛控制的重要性被训练伤患者相对低估,下一步应重点关注。结论Kano-IPA方法能够有效分析训练伤患者的需求属性,并确定优先改进顺序,为资源优化配置提供方向,有助于提升康复护理质量和训练伤患者满意度。 展开更多
关键词 KANO模型 康复 护理 干预策略 重要性-满意度分析
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基于Null Importance与GS-LGBM的糖尿病视网膜病变因素分析与风险预测 被引量:2
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作者 曹佳悦 罗冬梅 《中国医学物理学杂志》 CSCD 2023年第8期1033-1038,共6页
目的:通过机器学习算法分析糖尿病视网膜病变(DR)关键因素,构建DR风险预测模型,为DR的预防和诊断提供参考。方法:采用国家人口健康科学数据中心的《糖尿病并发症预警数据集》,基于Null Importance方法去除噪声特征,筛选出与DR有关的关... 目的:通过机器学习算法分析糖尿病视网膜病变(DR)关键因素,构建DR风险预测模型,为DR的预防和诊断提供参考。方法:采用国家人口健康科学数据中心的《糖尿病并发症预警数据集》,基于Null Importance方法去除噪声特征,筛选出与DR有关的关键因素;基于GridSearch优化LGBM模型参数,构建GS-LGBM DR风险预测模型。以准确率、精确率、召回率、F1分数、AUC值作为评价标准,与XGBoost、随机森林、Logistic以及未调优的LGBM模型进行比较。结果:Null Importance方法筛选出30个关键因素;与XGBoost、随机森林、Logistic以及未调优的LGBM模型相比,本研究所构建的GS-LGBM DR风险预测模型各评价指标均最优,其在测试数据上的AUC值高达0.897。结论:相较传统的DR预测模型,经过超参数优化后的模型具有更好的DR风险预测能力,更有助于DR的临床诊断。 展开更多
关键词 糖尿病视网膜病变 Null importance 风险预测 GS-LGBM
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Resilience based importance measure analysis for SoS 被引量:18
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作者 PAN Xing WANG Huixiong +1 位作者 YANG Yanjing ZHANG Guozhong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第5期920-930,共11页
In a system of systems(SoS),resilience is an important factor in maintaining the functionality,stability,and enhancing the operation effectiveness.From the perspective of resilience,this paper studies the importance o... In a system of systems(SoS),resilience is an important factor in maintaining the functionality,stability,and enhancing the operation effectiveness.From the perspective of resilience,this paper studies the importance of the SoS,and a resilience-based importance measure analysis is conducted to provide suggestions in the design and optimization of the structure of the SoS.In this paper,the components of the SoS are simplified as four kinds of network nodes:sensor,decision point,influencer,and target.In this networked SoS,the number of operation loops is used as the performance indicator,and an approximate algorithm,which is based on eigenvalue of the adjacency matrix,is proposed to calculate the number of operation loops.In order to understand the performance change of the SoS during the attack and defense process in the operations,an integral resilience model is proposed to depict the resilience of the SoS.From different perspectives of enhancing the resilience,different measures,parameters and the corresponding algorithms for the resilience importance of components are proposed.Finally,a case study on an SoS is conducted to verify the validity of the network modelling and the resiliencebased importance analysis method. 展开更多
关键词 system of systems (SoS) RESILIENCE network modelling importance MEASURE ANALYSIS operation LOOP
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Neural Networks Combined with Importance Sampling Techniques for Reliability Evaluation of Explosive Initiating Device 被引量:12
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作者 GONG Qi ZHANG Jianguo +1 位作者 TAN Chunlin WANG Cancan 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2012年第2期208-215,共8页
Concerning the issue of high-dimensions and low-failure probabilities including implicit and highly nonlinear limit state function, reliability analysis based on the directional importance sampling in combination with... Concerning the issue of high-dimensions and low-failure probabilities including implicit and highly nonlinear limit state function, reliability analysis based on the directional importance sampling in combination with the radial basis function (RBF) neural network is used, and the RBF neural network based on first-order reliability method (FORM) is to approximate the unknown implicit limit state functions and calculate the most probable point (MPP) with iterative algorithm. For good efficiency, based on the ideas that directional sampling reduces dimensionality and importance sampling focuses on the domain contributing to failure probability, the joint probability density function of importance sampling is constructed, and the sampling center is moved to MPP to ensure that more random sample points draw belong to the failure domain and the simulation efficiency is improved. Then the numerical example of initiating explosive devices for rocket booster explosive bolts demonstrates the applicability, versatility and accuracy of the approach compared with other reliability simulation algorithm. 展开更多
关键词 neural networks importance sampling explosive initiating device RELIABILITY NONLINEARITY
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