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基于改进K-means算法的室内可见光通信O-OFDM系统信道均衡技术
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作者 贾科军 连江龙 +1 位作者 张常瑞 蔺莹 《电讯技术》 北大核心 2025年第1期96-102,共7页
在室内可见光通信中符号间干扰和噪声会严重影响系统性能,K均值(K-means)均衡方法可以抑制光无线信道的影响,但其复杂度较高,且在聚类边界处易出现误判。提出了改进聚类中心点的K-means(Improved Center K-means,IC-Kmeans)算法,通过随... 在室内可见光通信中符号间干扰和噪声会严重影响系统性能,K均值(K-means)均衡方法可以抑制光无线信道的影响,但其复杂度较高,且在聚类边界处易出现误判。提出了改进聚类中心点的K-means(Improved Center K-means,IC-Kmeans)算法,通过随机生成足够长的训练序列,然后将训练序列每一簇的均值作为K-means聚类中心,避免了传统K-means反复迭代寻找聚类中心。进一步,提出了基于神经网络的IC-Kmeans(Neural Network Based IC-Kmeans,NNIC-Kmeans)算法,使用反向传播神经网络将接收端二维数据映射至三维空间,以增加不同簇之间混合数据的距离,提高了分类准确性。蒙特卡罗误码率仿真表明,IC-Kmeans均衡和传统K-means算法的误码率性能相当,但可以显著降低复杂度,特别是在信噪比较小时。同时,在室内多径信道模型下,与IC-Kmeans和传统Kmeans均衡相比,NNIC-Kmeans均衡的光正交频分复用系统误码率性能最好。 展开更多
关键词 可见光通信 光正交频分复用 多径信道 信道均衡 K-means算法 反向传播神经网络
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The Relationship between Psychological Vulnerability,Aging Attitudes and Life Meaning in Elderly Patients with Comorbidities
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作者 Jiaojiao Wu Dou Fu +8 位作者 Lili Zhang Xiangying Xie Xinmei Wang Xiangying Shen Shanshan Liu Xu Xu Hui Cheng Xiaojie Ma Doudou Lin 《International Journal of Mental Health Promotion》 2024年第11期897-904,共8页
Background:With the rapid aging of China’s population and the increasing prevalence of comorbidities in the elderly,psychological crises have become more common.This study aims to investigate the present status of ps... Background:With the rapid aging of China’s population and the increasing prevalence of comorbidities in the elderly,psychological crises have become more common.This study aims to investigate the present status of psychological vulnerability,aging attitudes,and life meaning in elderly patients with comorbidities.Methods:A total of 685 elderly inpatients and outpatients at Renmin Hospital of Wuhan University between July and December 2022 were selected using the simple random sampling method.Social demographic data were collected,and the Attitudes to aging Questionnaire(AAQ),the Chinese Life Meaning Questionnaire(C-MLQ),and the Psychological Vulnerability Scale(C-PVS)were used for the analysis.A total of 685 questionnaires were received,and 602 valid questionnaires were collected,with an effective rate of 87.88%.Data analysis was performed using SPSS V25.0 and AMOS V24.0.Results:The total scores of psychological vulnerability,aging attitudes,and life meaning were 69.4±12.8,80.2±13.5 and 39.2±8.3,respectively.The psychological vulnerability was significantly negatively correlated with life meaning and aging attitudes(r=-0.351,-0.264;p<0.01).There was a significant positive correlation between aging attitudes and life meaning(r=0.515;p<0.01).Life meaning played a partial mediating role between psychological vulnerability and aging attitudes(β=3.070,p<0.05).Conclusion:This study found that the psychological vulnerability in elderly patients with comorbidities was at the lower level,which was related to the elderly patients’aging attitudes and their current status of life meaning.The level of psychological vulnerability in elderly patients with senile-related comorbidities needs to be further improved.Medical workers should pay attention to the psychological vulnerability of elderly patients and improve the identification of psychological crises of such patients. 展开更多
关键词 The elderly COMORBIDITY life meaning psychological vulnerability aging attitudes
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A Cognitive Psychological Study on the Acquisition of Chinese Word’s Coloring Meaning--Chinese as a Second Language
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作者 LIU Yan 《Sino-US English Teaching》 2024年第5期217-221,共5页
Lexical meaning mainly includes rational meaning,grammatical meaning,and coloring meaning.Mastering the coloring meaning of vocabulary is of great significance for foreign students to use Chinese vocabulary correctly.... Lexical meaning mainly includes rational meaning,grammatical meaning,and coloring meaning.Mastering the coloring meaning of vocabulary is of great significance for foreign students to use Chinese vocabulary correctly.This study mainly examines the psychological mechanism of Chinese second language learners mastering the coloring meaning of words,examines the psychological characteristics of students mastering the color meaning of words from the perspectives of second language learning theory and cognitive theory,establishes a cognitive schema for coloring meaning learning,and proposes corresponding learning models and teaching strategies. 展开更多
关键词 Chinese vocabulary acquisition coloring meaning COGNITION
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Exploring the meaning of care among lived experiences of patients with blindness:an interpretive phenomenological study
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作者 Mohammad Ali Mohammadi Mehdi Heidarzadeh +1 位作者 Saeed Mehri Mahmood Shamshiri 《Frontiers of Nursing》 2024年第3期319-326,共8页
Objective:To explore the meaning of care experienced by people with blindness in hospitals.Methods:Interpretive phenomenology along with the 6-step method of van Manen was used to conduct the study.Using purposeful sa... Objective:To explore the meaning of care experienced by people with blindness in hospitals.Methods:Interpretive phenomenology along with the 6-step method of van Manen was used to conduct the study.Using purposeful sampling,15 people with legal blindness were interviewed.Thematic analysis was used to isolate the meaning of care.Results:Five themes emerged:(a)nurses in the eyes of patients with blindness;(b)negligence in the caring moments;(c)being cared for in ambiguity;(d)Uncoordinated care;and(e)Psychological discomfor t.These sub-themes were condensed into an overarching theme titled as“marginalized patients inside the stereotypical healthcare system.”Conclusions:Lived experiences of patients with blindness revealed that hospitals provide stereotypic or inappropriate care for this minority group in society.Health professionals par ticularly nurses should be skilled to provide person-centered and coordinated care for patients with blindness. 展开更多
关键词 HOSPITALIZATION lived experience meaning of care people with blindness PHENOMENOLOGY
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基于K-means/RPF的大型遮蔽空间人员定位算法
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作者 白泽坤 苏中 吴学佳 《传感器与微系统》 北大核心 2025年第1期157-160,164,共5页
针对大型遮蔽空间惯性/地图匹配算法中粒子贫化和子粒子群迷路效应导致定位精度下降的问题,提出一种基于K-means聚类的回溯粒子滤波(RPF)人员定位算法。首先,用行人航位推算(PDR)中航向更新、步频检测及步长估计得到初始运动轨迹;然后,... 针对大型遮蔽空间惯性/地图匹配算法中粒子贫化和子粒子群迷路效应导致定位精度下降的问题,提出一种基于K-means聚类的回溯粒子滤波(RPF)人员定位算法。首先,用行人航位推算(PDR)中航向更新、步频检测及步长估计得到初始运动轨迹;然后,设计RPF算法,提高存活粒子有效性和多样性,缓解粒子贫化,提高人员定位精度;最后,通过K-means聚类算法解决子粒子群的迷路效应,修正人员轨迹出现在非可行域的现象。实验结果表明:本文算法抑制了粒子贫化和子粒子群迷路效应,人员平均定位误差相比惯性定位和标准粒子滤波降低了81.20%和51.48%。 展开更多
关键词 大型遮蔽空间 K-meanS聚类 回溯粒子滤波 粒子贫化 迷路效应
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我国公共图书馆发展水平的K-means聚类分析
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作者 熊朝松 《江苏科技信息》 2025年第2期71-74,115,共5页
文章首先基于第七次全国县级以上公共图书馆评估定级上等级馆名单数据,统计我国31个省市自治区公共图书馆进入一级图书馆、二级图书馆、三级图书馆以及未定等级数量,计算出比例;随后基于比例数据,利用K-means聚类分析算法对我国31个省... 文章首先基于第七次全国县级以上公共图书馆评估定级上等级馆名单数据,统计我国31个省市自治区公共图书馆进入一级图书馆、二级图书馆、三级图书馆以及未定等级数量,计算出比例;随后基于比例数据,利用K-means聚类分析算法对我国31个省市自治区进行数据分析,用来研究我国公共图书馆发展水平情况。数据分析结果显示,我国31个省市自治区公共图书馆发展水平可以分为3个档次:领先水平,包括北京等8地;中等水平,包括河北等17地;落后水平,包括辽宁等6地。最后,文章根据聚类分析结果提出了助力我国公共图书馆高质量均衡发展的相关建议与看法。 展开更多
关键词 公共图书馆 发展水平 K-means聚类分析
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基于K-means的海南物流职业本科学生学习行为分析
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作者 李芸嘉 《物流科技》 2025年第3期178-181,共4页
在现代物流行业中,培养具备全面专业知识和实践能力的物流职业本科学生至关重要。为了更好地了解学生在学习过程中的行为和学习习惯,文章将采用K-means聚类模型方法,对现代物流管理(职业本科)学生的学习行为进行深入探索与分类。通过这... 在现代物流行业中,培养具备全面专业知识和实践能力的物流职业本科学生至关重要。为了更好地了解学生在学习过程中的行为和学习习惯,文章将采用K-means聚类模型方法,对现代物流管理(职业本科)学生的学习行为进行深入探索与分类。通过这项研究,旨在为优化物流教育、提高学生学习效果提供有益的参考建议。文章将介绍研究设计、数据收集与处理方法,并对结果进行解析与讨论。 展开更多
关键词 物流 职业本科 学情分析 K-meanS聚类
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基于K-Means++算法和改进遗传算法的维保站维修调度方法的研究
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作者 何晨曦 《科学技术创新》 2025年第3期49-52,共4页
传统的电梯维保工作模式是定期保养,即针对每台电梯而言,需要每半个月去保养一次,然而电梯设备的分布和保养进度的复杂性决定了人为排定的维保路线不能够最大限度地解决维保资源。为此提出基于K-Means++算法和改进遗传算法的维保站维修... 传统的电梯维保工作模式是定期保养,即针对每台电梯而言,需要每半个月去保养一次,然而电梯设备的分布和保养进度的复杂性决定了人为排定的维保路线不能够最大限度地解决维保资源。为此提出基于K-Means++算法和改进遗传算法的维保站维修调度方法,首先使用分解法的思想将问题进行拆分,然后采用K均值聚类算法将维保任务分配到合适的维保站,建立总路程最短的维保调度模型,最后利用改进遗传算法进行求解,获取最优路线规划结果,对缩减维保工作时间,提升维保工作效率,从而提升电梯使用的安全性和可靠性有一定的意义。 展开更多
关键词 电梯维保 维保调度 分解法 K-means++算法 改进遗传算法
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基于改进K-means聚类算法的分布式储能集群划分方法
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作者 刘春雨 《东北电力技术》 2025年第1期1-5,共5页
随着规模化分布式电源及储能的接入,配电网的功率返送、节点过电压等问题愈加显著,对电网规划、运行监视和调度控制等造成一定影响,也不利于储能大范围发展。为此提出一种适用于规模化分布式储能的集群划分方法,基于功率节点电压灵敏度... 随着规模化分布式电源及储能的接入,配电网的功率返送、节点过电压等问题愈加显著,对电网规划、运行监视和调度控制等造成一定影响,也不利于储能大范围发展。为此提出一种适用于规模化分布式储能的集群划分方法,基于功率节点电压灵敏度的电气距离模块度指标,对经典K-means算法进行改进,设计节点指数法、肘部法则优化初始聚类中心选择和集群数确定。以IEEE33系统算例进行验证,结果表明所提集群划分方法具有较强的电气耦合性、准确性和运算效率。 展开更多
关键词 分布式储能 集群划分 配电网结构 K-meanS聚类算法 划分指标
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An Exploration of Interpersonal Meanings in Advertising Discourse from Functional Grammar Perspective 被引量:1
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作者 刘瑜 樊燕龙 《Sino-US English Teaching》 2007年第1期40-45,共6页
Interpersonal function is one of the three metafunctions of language. This paper investigates the interpersonal meanings in Chinese cosmetic advertising discourse from mood, modality and appraise the three aspects. Ba... Interpersonal function is one of the three metafunctions of language. This paper investigates the interpersonal meanings in Chinese cosmetic advertising discourse from mood, modality and appraise the three aspects. Based on an exploratory study of data of six typical Chinese cosmetic advertising discourses, the paper claims that the distribution of mood and modality has close link with the interpersonal meaning in advertising. The Functional Grammar and Appraisal System help to reveal the interpersonal meanings of the discourse concerned. 展开更多
关键词 interpersonal meaning functional grammar appraisal system
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Symbolic Meanings of “Rose” in A Rose for Emily 被引量:1
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作者 夏祖贵 《英语广场(学术研究)》 2012年第8期42-45,共4页
A Rose for Emily is one of William Faulkner's most famous short stories.Through the representing of patriarchy influence on Emily,Faulkner shows his readers Emily's tragic life.From the diverse meanings of the... A Rose for Emily is one of William Faulkner's most famous short stories.Through the representing of patriarchy influence on Emily,Faulkner shows his readers Emily's tragic life.From the diverse meanings of the "Rose" to the debated themes,this story has been discussed before.This paper tries to analyze the three stages of Emily's struggle for love in order to represent the symbolism of the "Rose" from the perspective of feminism.It also represents the root of Emily's tragedy and the sympathy for the tragic fate of the Southern women. 展开更多
关键词 A ROSE for EMILY SYMBOLIC meaningS PATRIARCHY FEMINISM
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The Processing Mechanism of Associative Meaning Under the Cognitive Context Based on Culture 被引量:1
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作者 许葵花 《Sino-US English Teaching》 2006年第8期48-52,41,共6页
Cognitive context is the cognitionalized context of language, situation and context of culture by the individual which is stored and stimulated in individual's mind when meaning is processed. The focus of this articl... Cognitive context is the cognitionalized context of language, situation and context of culture by the individual which is stored and stimulated in individual's mind when meaning is processed. The focus of this article is on context of culture cognitionalized by individuals. Cognitive context based on culture is the inner force of the processing of associative meaning. Cognitive context reflects the similarities and differences of the understanding of different cultural communities towards the world around them. 展开更多
关键词 cognitive context associative meaning CULTURE
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THEORY AND IMPLEMENTATION OF ICAI COGNITIVE MODEL BASED ON MEANING
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作者 何丕廉 侯越先 《Transactions of Tianjin University》 EI CAS 1999年第2期36-39,共4页
Cognitive models must be able to adapt the students learning behaviors dynamically.In our point of view,the processes of learning and understanding are,in nature,the procedure that gains the meaning of the object to b... Cognitive models must be able to adapt the students learning behaviors dynamically.In our point of view,the processes of learning and understanding are,in nature,the procedure that gains the meaning of the object to be learned.So,ICAI cognitive models should reflect the meaning structure of the domain knowledge in students mind.According to this view,we developed the meaning theory of Ludwig Wittgenstein,and proposed the concept of meaning conjoinism.On the basis of the meaning conjoinism we proposed a meaning oriented ICAI cognitive model and its corresponding teaching tactics.Furthermore,we developed an ICAI system named Thinking and the efficiency of our proposal has been demonstrated. 展开更多
关键词 meaning oriented meaning conjoinism cognitive model teaching tactics ICAI
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Translating Means Translating Meaning
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作者 李海燕 《内蒙古大学学报(哲学社会科学版)》 CSSCI 2000年第S1期170-173,共4页
美国著名翻译理论家尤金·奈达说 :“翻译即译意 (Translating m eans translating m eaning)。”就实质而言 ,翻译即译意。就是把一种语言表达的意义用另一种语言表达出来。翻译分理解与表达两个步骤。理解是翻译的基础 ,表达直接... 美国著名翻译理论家尤金·奈达说 :“翻译即译意 (Translating m eans translating m eaning)。”就实质而言 ,翻译即译意。就是把一种语言表达的意义用另一种语言表达出来。翻译分理解与表达两个步骤。理解是翻译的基础 ,表达直接决定译文的成败与优劣 。 展开更多
关键词 TRANSLATING meaning UNDERSTANDING EXPRESSION
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Cultural Context and Associative Meaning of Words in Cross-culture Communication
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作者 吴玉侠 董艇舰 《英语广场(学术研究)》 2014年第12期132-133,共2页
Language is the vehicle of culture, vocabulary is the most active part of a language. This article compares and analyses the relationship of cultural context and the associative meaning of words in three aspects—asso... Language is the vehicle of culture, vocabulary is the most active part of a language. This article compares and analyses the relationship of cultural context and the associative meaning of words in three aspects—associative meaning overlap, associative meaning mismatch and associative meaning gap, revealing its importance in the cross-cultural communication. 展开更多
关键词 associative meaning cultural context CROSS-CULTURE
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Associative Meanings of Colors in Chinese and English Cultures
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作者 杨楠 王晓玲 李海丽 《海外英语》 2011年第3X期164-166,共3页
Colors are endowed into many different associative meanings by different peoples and countries under the various cultural backgrounds and people make it express testimonial and depreciated meaning. There is not only t... Colors are endowed into many different associative meanings by different peoples and countries under the various cultural backgrounds and people make it express testimonial and depreciated meaning. There is not only the same aspect, but also the differences. Moreover, some factors such as geographical environment, public sentiment custom, thinking mode, religious belief, and national psychology also influence it. Each kind of color is regarded the difference for every nation's person. This article analyzes and investigates the associative meaning of the color in the Chinese and English cultures. And then it will let the reader learn well and more the associative meaning under the different cultural background. 展开更多
关键词 ASSOCIATIVE meaningS COLORS CULTURES
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On the Meaning of the Number SEVEN in the Eastern and Western Culture
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作者 涂朝莲 陈坤 《海外英语》 2011年第4X期276-276,284,共2页
This paper interprets the connotation,denotation and the symbolic meaning of SEVEN from the perspective of semiotics.The number SEVEN means samsara,destiny,reincarnation,the ending and a brand new beginning,satisfacti... This paper interprets the connotation,denotation and the symbolic meaning of SEVEN from the perspective of semiotics.The number SEVEN means samsara,destiny,reincarnation,the ending and a brand new beginning,satisfaction after a lot of suffering in the East.While,in the West,besides these,it refers to the magic and holy power of the God,mystery,completeness and perfection,occult,happiness and luck. 展开更多
关键词 the NUMBER SEVEN CULTURE meaning numerology SEMIOTICS
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Meaning and the Theory of Speech Acts
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作者 孙丽 吴小梅 《语言与文化研究》 2008年第2期43-46,共4页
According to J.L.Austin and J.R.Searle Speech Act Theory,many actions can actually be performed with words that is to say an important part of the meaning of an utterance is what that utterance does.Language is not on... According to J.L.Austin and J.R.Searle Speech Act Theory,many actions can actually be performed with words that is to say an important part of the meaning of an utterance is what that utterance does.Language is not only used to inform or describe things,it is often used to "do things".The utterances are of three kinds of acts:Locutionary Act,Illocutionary Act,and Perlocutionary Act which are performed simultaneously.Through the study,we see that speech can be far beyond the level of language system. 展开更多
关键词 utterance ACT meaning
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The Role of Context in Interpreting Word Meaning
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作者 孙晓燕 刘红梅 《科技信息》 2009年第1期239-,共1页
Meaning is a central topic in semantics,but it exists in context.Context plays an important role in interpreting word meaning. It will be analyzed as follows:(1) Context determines the referents of deictic words;(2) C... Meaning is a central topic in semantics,but it exists in context.Context plays an important role in interpreting word meaning. It will be analyzed as follows:(1) Context determines the referents of deictic words;(2) Context eliminates word ambiguity;(3) Context provides clues for interference of word meaning. 展开更多
关键词 meaning CONTEXT referents AMBIGUITY HYPONYMY
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On the priority of salient meanings in English idioms understanding
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作者 冯丽颖 《Sino-US English Teaching》 2009年第4期45-51,共7页
Giora proposed that general principle of salience: salient comprehension of figurative and meanings are processed first and literal language be governed by a more meaning salience determines the type of processing in... Giora proposed that general principle of salience: salient comprehension of figurative and meanings are processed first and literal language be governed by a more meaning salience determines the type of processing invoked. According to the Graded Salience Hypothesis, processing familiar metaphors should involve the activation of both their metaphoric and literal meanings, regardless of the type of context in which they are embedded. Processing less familiar metaphors should activate the literal meaning in both types of contexts; however, in the literally biased context, it should be the only one activated. Processing familiar idioms in context biased towards the idiomatic meaning should evoke their figurative meaning almost exclusively, because their figurative meaning is much more salient than their literal meaning. However, processing less familiar idioms in an idiomatic context should activate both their literal and idiomatic meanings because both meanings enjoy similar salience status. 展开更多
关键词 the Graded Salient Hypothesis salience status idiomatic meaning literal meaning
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