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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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Meaning in Life and Mental Health Issues in Older Adults:A Meta-Analysis
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作者 Shu Nie Jiyoon Lim +2 位作者 Xintian Xu Lei Zheng Yiqun Gan 《International Journal of Mental Health Promotion》 2023年第9期971-984,共14页
This study aims to be the first to use meta-analysis to explore the relationship between meaning in life(MIL)and mental health issues among older adults.A meta-analysis was conducted using six databases,resulting in 1... This study aims to be the first to use meta-analysis to explore the relationship between meaning in life(MIL)and mental health issues among older adults.A meta-analysis was conducted using six databases,resulting in 16 studies with 5,074 participants in total.The“metacor”and“forestplot”packages in R-Studio were used for data analysis.The total effect was calculated using a random-effects model,with I2=86%in the heterogeneity test.The results showed a moderate negative correlation between MIL and mental health issues among older adults,with an average effect of−0.37.Five potential moderating variables were examined:the conceptualization of MIL(value vs.purpose),region(Asian vs.Western countries),residence status(community vs.nursing home vs.hospital),types of mental health issues,and evaluation methods(clinical vs.non-clinical).The first four had no significant moderating effect.The mean correlation coefficients between mental health issues and value/purpose were−0.49/−0.33;the mean correlation coefficients in Asian countries and Western countries were−0.48 and−0.34;the mean correlation coefficients among participants living in community/nursing home/mixed status were−0.33/−0.40/−0.40;the mean correlation coefficients between MIL and depression/others were−0.37/−0.35;however,the negative relationship between MIL and mental health issues was stronger when non-clinical evaluations(self-report only)were used.Specifically,the mean correlation coefficient for non-clinical evaluations was−0.42 and for clinical evaluations was−0.29.This study is the first meta-analysis to identify the negative correlation between older adults’MIL and mental health issues.Significant moderating effects of evaluation methods were found. 展开更多
关键词 meaning in life mental health issues DEPREssION ANXIETY META-ANALYsIs older adults
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Crystalline and amorphous metal sulfide composite electrode materials with long cycle life:Preparation and performance of hybrid capacitors
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作者 DING Ning WANG Siyu +4 位作者 YU Shihua XU Pengcheng HAN Dandan SHI Dexin ZHANG Chao 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1784-1794,共11页
Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realiz... Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realized the defect regulation of crystal NiCo_(2)S_(4) in the core.Taking advantage of the flexible protection of an amor-phous shell and the high capacity of a conductive core with defects,the v-NCS@MS electrode exhibited high specif-ic capacity(1034 mAh·g^(-1) at 1 A·g^(-1))and outstanding rate capability.Moreover,a hybrid supercapacitor was assembled with v-NCS@MS as cathode and activated carbon(AC)as anode,which can achieve remarkably high specific energy of 111 Wh·kg^(-1) at a specific power of 219 W·kg^(-1) and outstanding capacity retention of 80.5%after 15000 cycling at different current densities. 展开更多
关键词 crystalline@amorphous heterostructure NiCo2s4@Mos2 hybrid supercapacitor defect design long cycle life
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Effects of supervised movie appreciation on the improvement of college students’ life meaning sense 被引量:15
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作者 Xinqiang Wang Dajun Zhang +2 位作者 Jinliang Wang Hui Xu Min Xiao 《Health》 2010年第7期804-810,共7页
The purpose of this study was to explore the effects of supervised movie appreciation on improving the life meaning sense among college students. The intervention combined by “pre-video, post counseling” was conduct... The purpose of this study was to explore the effects of supervised movie appreciation on improving the life meaning sense among college students. The intervention combined by “pre-video, post counseling” was conducted on the experimental group, while the control group received no intervention. Results have shown that the scores on the subscales of will to meaning, life purpose, life control, suffer acceptance and on the total scale have improved significantly. No gender difference was found on the intervention effect, and participants receiving intervention maintained higher level on related subscales a week later, indicating that supervised movie appreciation is an effective way to improve the life meaning sense among college students. 展开更多
关键词 College students life meaning sENsE supervised MOVIE APPRECIATION sUICIDE Prevention MENTAL Health Education
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Meaning in life and well-being of older stroke survivors in Chinese communities: Mediating effects of mastery and self-esteem 被引量:1
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作者 Jingjin Shao Jiliang Shen +1 位作者 Qinghua Zhang Tian Lin 《Health》 2013年第4期743-748,共6页
The study aims to examine the role of mastery and self-esteem as a potential mediator of the relationship of meaning in life and well-being among older Chinese stroke survivors. A cross-sectional study was conducted i... The study aims to examine the role of mastery and self-esteem as a potential mediator of the relationship of meaning in life and well-being among older Chinese stroke survivors. A cross-sectional study was conducted in 214 community-dwelling older stroke survivors (128 men and 86 women), ranging from 60 years to 88 years old. The meaning in life, mastery, self-esteem and subjective well-being were measured. The results indicated that: 1) The meaning in life and subjective well-being of stroke survivors were significantly positive correlated;2) Mastery and self-esteem played partial mediating roles between existential vacuum and subjective well-being;Self-esteem played full a mediating role between suffer acceptance and subjective well-being;Mastery played a full mediating role between life control and subjective well-being;Mastery played a partial mediating role between death acceptance and subjective well-being;Self-esteem also played a partial mediating role between mastery and subjective well-being. 展开更多
关键词 sTROKE meaning in life MAsTERY sELF-EsTEEM WELL-BEING
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Life′s Simple 7干预减轻Her⁃2阳性乳腺癌患者化疗相关心血管系统损害的研究 被引量:2
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作者 吴军 崔伟燕 +2 位作者 李平 张青凤 欧月珍 《实用医学杂志》 CAS 北大核心 2023年第13期1647-1651,1656,共6页
目的探讨Life′s Simple 7(LS7)干预减轻Her⁃2阳性乳腺癌患者根治术后化疗相关心血管系统损害的作用。方法将120例Her⁃2阳性并接受标准化乳腺癌化疗的患者随机等量分为对照组及LS7组,对照组为标准化疗方案,LS7组为对照组基础上给予LS7干... 目的探讨Life′s Simple 7(LS7)干预减轻Her⁃2阳性乳腺癌患者根治术后化疗相关心血管系统损害的作用。方法将120例Her⁃2阳性并接受标准化乳腺癌化疗的患者随机等量分为对照组及LS7组,对照组为标准化疗方案,LS7组为对照组基础上给予LS7干预12个月,后续通过比较两组治疗前后心血管系统损伤程度、焦虑、抑郁及生活质量等指标评价其对心血管系统损害的改善作用。结果相较于对照组,LS7组LS7总评分及7项心血管健康指标均优于对照组(P<0.05),LS7组LVEF较高(P<0.05)、NT⁃proBNP较低(P<0.05),焦虑和抑郁评分较低(P<0.05)、生活质量评分较高(P<0.05)。结论LS7干预可显著减轻Her⁃2阳性乳腺癌化疗相关心血管系统损害并改善乳腺癌患者的心理状况和生活质量,值得在临床推广。 展开更多
关键词 lifes simple 7 乳腺癌 心血管健康 心理状况 生活质量
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Mindfulness Associates Life Satisfaction:The Mediating Role of Internal Control and the Presence of Meaning in Life
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作者 Zihui Yuan Yanhui Xiang Ziyuan Chen 《International Journal of Mental Health Promotion》 2021年第1期15-25,共11页
This study explored the internal mechanism of the effect of mindfulness on life satisfaction from the perspective of logotherapy theory and achievement attribution theory.We recruited 1021 college students using a com... This study explored the internal mechanism of the effect of mindfulness on life satisfaction from the perspective of logotherapy theory and achievement attribution theory.We recruited 1021 college students using a combination of random sampling and cluster sampling.They completed the relevant questionnaire.The results showed that,from the perspective of logotherapy theory,wefind that the presence of meaning in life is an important intermediary between mindfulness and life satisfaction.From the perspective of achievement attribution theory,we found that internal control was an important intermediary between mindfulness and life satisfaction.In addition,we also found the chain mediating path that mindfulness positively predicted life satisfaction by influencing internal control and then influencing the presence of meaning in life.This study proves for thefirst time that the theory of logotherapy and achievement attribution explain the internal mechanism of the relation of mindfulness on life satisfaction.This study provides an important reference for how to effectively improve life satisfaction from the perspective of mindfulness. 展开更多
关键词 MINDFULNEss life satisfaction the presence of meaning in life internal control structural equation model
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Depression by the Theory of Breathing and Finding Meaning of Life
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作者 Nadia Khalid Al-Khalidi Hamad Al-Tayyar 《Journal of Behavioral and Brain Science》 2021年第12期286-300,共15页
This study aimed to examine the relationship of finding meaning to life with the level of depression and investigates the effect of using breathing theory in treating or reducing depression in a sample of individuals ... This study aimed to examine the relationship of finding meaning to life with the level of depression and investigates the effect of using breathing theory in treating or reducing depression in a sample of individuals suffering from depression in the Kuwait Mental Health Center. In order to achieve these objectives, the researcher used the descriptive and analytical approach through an applied questionnaire on the study sample which consist of (380) individuals and the quasi-experimental approach by dividing the study sample individuals into two groups;control group consisted of (190) individuals and experimental group consist of (190) individuals. Also, the researcher developed meaning of life scale and breathing strategy, also used beck depression inventory scale. The study found a set of results, there is a negative relationship between finding meaning in life and depression and there are statistically significant differences between the members of the two groups due to the use of the breathing strategy, in favor of the experimental group. In the light of this result, the study came out with a set of recommendations, the most important of which are holding training and educational courses for depressed patients on ways and methods of finding meaning in life, as these courses have the benefit in reducing the level of depression among patients. 展开更多
关键词 DEPREssION Theory of Breathing Finding meaning of life KUWAIT
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The Ethics and the Meaning of Life among College Students
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作者 Maria Helena de Agrela Goncalves Jardim Geraldo Bezerra da Silva Junior +2 位作者 Marcia Lucia Sousa Dias Alves Bruna Raquel Figueira Ornelas de Gouveia Rita Baptista Silva 《International Journal of Clinical Medicine》 2018年第4期221-233,共13页
The concern of the ethics and the meaning of life in young adults became universal and are present in all contexts of human life. Such universality is due to the development of modern rationality, to establish a relat... The concern of the ethics and the meaning of life in young adults became universal and are present in all contexts of human life. Such universality is due to the development of modern rationality, to establish a relationship between the intrinsic theoretical dimensions (scientific) and practical dimensions (ethical), originated that are present in the own array of knowledge. This descriptive cross-sectional study, aims to identify the values of the ethical dimension and meaning of life defended by the college students of the Universities of Madeira, Portugal and Fortaleza, Brazil. The sample consists of 605 University students (Madeira = 225 and Fortaleza = 380), with an average age of 21 years and a standard deviation of 2. We used the questionnaire on values (adapted from the European Values Survey). Most of the young people referred to have a religion (60% wood and 78.4% stronghold), being the most Catholic, however, present in your frequency disinterest and, yet, in Brazil there is a greater diversity of religions. Supporting the intervention of religious institutions in situations of everyday life is accepted mostly by Brazilians, with the exception of politics (35.5%). On the other hand, the university students of the University of Madeira understand that Religious Institutions should only give their opinion on racial discrimination (76.6%). Believe in God (90.8% and 55.1% Stronghold) and Soul (80.3% and 66.4% Stronghold) are beliefs more referred to by college students. These results are intended to contribute in the field of research on ethical values and meaning of life in young people. This study contributes to future comparative research among university students and to developing strategic programs in education and health, increasing the success and excellence in the formation of a full citizenship, preventing the fanaticisms and the social discrimination that today devastate the collective globally. 展开更多
关键词 VALUEs ETHICs meaning of life Young Adults College students Questionnaire on Values (QsV)
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基于断裂力学的腐蚀钢丝疲劳S-N曲线研究 被引量:1
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作者 叶华文 叶杨帆 +2 位作者 邓雪峰 杨军川 徐勋 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2024年第5期1990-2000,共11页
高强冷拔钢丝因其优异的力学性能被广泛应用于缆索承重结构,服役过程中钢丝腐蚀与断裂威胁着结构安全。钢丝腐蚀后表面的蚀坑因应力集中效应易产生疲劳裂纹,因此腐蚀钢丝剩余疲劳寿命主要取决于裂纹的扩展阶段,且裂纹扩展受到腐蚀程度(... 高强冷拔钢丝因其优异的力学性能被广泛应用于缆索承重结构,服役过程中钢丝腐蚀与断裂威胁着结构安全。钢丝腐蚀后表面的蚀坑因应力集中效应易产生疲劳裂纹,因此腐蚀钢丝剩余疲劳寿命主要取决于裂纹的扩展阶段,且裂纹扩展受到腐蚀程度(初始损伤)的显著影响。精确表征腐蚀程度并准确评估服役期钢丝腐蚀后的剩余寿命,仍是亟待解决的维修难题。首先采用蚀坑最大深度表征钢丝腐蚀程度,以应力强度因子幅作为裂纹扩展驱动力指标,基于断裂力学的Paris公式建立受拉钢丝裂纹扩展理论模型,进而推导腐蚀钢丝的疲劳S-N曲线。大量既有的腐蚀钢丝疲劳试验结果与理论预测值的比较验证了所提理论模型及疲劳S-N曲线的合理性和有效性。含多个蚀坑的钢丝裂纹扩展有限元模拟表明,等效单裂纹适用于多腐蚀坑钢丝疲劳寿命的简化分析。参数分析表明,蚀坑深度和腐蚀环境是腐蚀钢丝疲劳强度的关键影响因素,而应力比和疲劳加载频率影响较小,所提出的S-N曲线在钢丝常规服役条件下适用于评估其剩余寿命,可得到合理的预测结果。基于断裂力学所提的理论方法和疲劳S-N曲线可为腐蚀钢丝的疲劳强度和寿命评估提供参考。 展开更多
关键词 冷拔钢丝 腐蚀 剩余寿命 s-N曲线 蚀坑深度
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基于D-S证据理论的岩爆预测方法研究 被引量:1
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作者 高永涛 朱强 +1 位作者 吴顺川 王勇兵 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第2期244-251,共8页
为了有效预测岩爆,提出基于D-S证据理论的岩爆预测方法.首先,选取与岩爆发生相关的6个指标因素作为证据体,并通过模糊物元框架和正态型隶属度函数构建证据体的基本概率分配.然后,利用K均值将证据体分类,并提出簇内证据用传统方式融合而... 为了有效预测岩爆,提出基于D-S证据理论的岩爆预测方法.首先,选取与岩爆发生相关的6个指标因素作为证据体,并通过模糊物元框架和正态型隶属度函数构建证据体的基本概率分配.然后,利用K均值将证据体分类,并提出簇内证据用传统方式融合而簇间证据用权重方式融合的组合融合规则,以减轻高冲突证据融合的不利影响.最后,将模型应用在秦岭终南山公路隧道2号竖井工程,且与经验方法对比.为了分析预测过程的不确定性和估计岩爆发生概率,采用蒙特卡洛模拟进行抽样仿真,并通过Spearman秩相关系数衡量输入指标的全局敏感性.研究结果表明:输入指标在不同的岩爆案例的影响程度差异较大且方向不同;5个岩爆案例的发生概率在40.8%~70.1%之间.该模型表现出优异的预测分类性能,可为深埋地下工程岩爆预测提供参考. 展开更多
关键词 岩石力学 岩爆预测 D-s证据理论 模糊物元 K均值
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基于最优k值k-means聚类分析的湖相沉积土层岩土参数分布研究 被引量:1
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作者 阮永芬 李鹏辉 +3 位作者 张虔 朱强 王勇 闫明 《贵州大学学报(自然科学版)》 2023年第2期89-96,共8页
对岩土参数进行传统的k-means聚类分析时,因无法确定k值,而导致无法有效剔除误差数据。为得到岩土参数可靠取值范围,基于最优k值的k-means算法进行研究,通过量化样本内距离和聚类紧密性来确定聚类数目k值,避免了传统k值的随机选取。对... 对岩土参数进行传统的k-means聚类分析时,因无法确定k值,而导致无法有效剔除误差数据。为得到岩土参数可靠取值范围,基于最优k值的k-means算法进行研究,通过量化样本内距离和聚类紧密性来确定聚类数目k值,避免了传统k值的随机选取。对粉土的三个基本物理力学指标:黏聚力c、内摩擦角φ、压缩模量E_(s)进行空间聚类分析。通过比较不同k值时的E_(E)值,确定最优k值为5。聚类完成后,原样本被划分为5类子样本。样本数量最多的一类为最优子样本,这类子样本与原样本分布一致,且数量偏离程度及变异性较小。对除最优类外的其他四类子样本进行分布检验,可知A-D检验法适用于小样本,而K-S检验法适用于大样本。根据偏度系数c值,调整合适的区间长度,进一步优化参数取值范围,并与工程实际采用值对比,检验方法的可行性。该分析方法实现由小样本代替大样本进行参数统计分析求取可靠的取值区间,简化计算,提高工作效率。 展开更多
关键词 K-means 粉土 正态分布 对数正态分布 K-s检验 A-D检验
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经皮二氧化碳分压监测在硬质支气管镜下Feng′s EBUS-TBNB中的应用
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作者 骆玉兔 孙亚楠 +1 位作者 潘家华 万南生 《南通大学学报(医学版)》 2024年第1期45-48,共4页
目的:探讨经皮二氧化碳分压(transcutaneous partial pressure of carbon dioxide,PtcCO_(2))监测在硬质支气管镜下冯氏气管内超声引导纵隔切开活检(Feng′s endobronchial ultrasound-guided transbronchial node biopsy,Feng′s EBUS-... 目的:探讨经皮二氧化碳分压(transcutaneous partial pressure of carbon dioxide,PtcCO_(2))监测在硬质支气管镜下冯氏气管内超声引导纵隔切开活检(Feng′s endobronchial ultrasound-guided transbronchial node biopsy,Feng′s EBUS-TBNB)中的应用。方法:收集2019年8月—2022年8月期间天津医科大学总医院收治的纵隔疾病患者128例,随机分成Feng′s EBUS-TBNB组和支气管内超声引导针吸活检术(endobronchial ultrasound-guided transbronchial needle aspiration,EBUS-TBNA)组,患者均予高频喷射通气行硬质支气管镜下操作及PtcCO_(2)监测,EBUS-TBNA组患者行EBUS-TBNA,Feng′s EBUS-TBNB组患者行Feng′s EBUS-TBNB术,比较两组患者术前(T0)、通气开始时(T_(1))、通气10 min后(T_(2))、通气20 min后(T3)、通气30 min后(T_(4))、通气40 min后(T_(5))、通气50 min后(T_(6))、通气60 min后(T_(7))心率(heart rate,HR)、平均动脉压(mean arterial pressure,MAP)和PtcCO_(2)的变化。结果:T_(1)~T_(7)时,两组患者HR、MAP和PtcCO_(2)水平均明显高于T0时(P<0.05)。T0~T_(2)时,两组患者HR、MAP和PtcCO_(2)水平比较差异无统计学意义(P>0.05);T3~T_(5)时,Feng′s EBUS-TBNB组HR、MAP和PtcCO_(2)水平均明显高于EBUS-TBNA组(P<0.05);而T_(6)~T_(7)时,两组患者HR、MAP和PtcCO_(2)水平比较差异无统计学意义(P>0.05)。结论:将PtcCO_(2)应用于Feng′s EBUS-TBNB中,可间接反映患者HR、MAP水平变化,值得临床推广应用。 展开更多
关键词 纵隔疾病 经皮二氧化碳分压 硬质支气管镜 冯氏气管内超声引导纵隔切开活检 心率 平均动脉压
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液压成形对液体火箭发动机多层增强S型波纹管结构疲劳寿命的影响 被引量:1
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作者 张涵 张东升 朱卫平 《火箭推进》 CAS 北大核心 2024年第1期113-126,共14页
完善液体火箭发动机燃气摇摆装置中增强S型波纹管组件的疲劳寿命评估方法,提高其疲劳寿命预测精度,是发展可重复使用液体火箭发动机的重要课题之一。针对多层增强S型波纹管,为了计算其液压成形后的实际寿命数据,了解成形工艺对其疲劳寿... 完善液体火箭发动机燃气摇摆装置中增强S型波纹管组件的疲劳寿命评估方法,提高其疲劳寿命预测精度,是发展可重复使用液体火箭发动机的重要课题之一。针对多层增强S型波纹管,为了计算其液压成形后的实际寿命数据,了解成形工艺对其疲劳寿命的影响,提出一种充分考虑成形制备过程对结构不同区域几何构型和材料力学性能造成差异化影响后的波纹管疲劳寿命分析方法。该方法基于成形仿真和材料拉伸试验结果,构建实际波纹管有限元模型并进行三维仿真分析,得到其在高内压和不同摆动工况下结构危险点的循环载荷信息,并根据波纹管结构的低周疲劳失效特点采用子午向应力应变数据,以及经过平均应力应变修正的Manson-Coffin(M-C)公式对波纹管的循环寿命进行估算和对比分析。结果表明:波纹管疲劳寿命薄弱点位置和大小均与循环摆角有关;在预测计算中考虑液压成形作用影响更接近实际场景,所得结构疲劳寿命大小和所在区域均与理论模型值存在差异,在结构设计、优化和健康监测中不应忽视其影响。 展开更多
关键词 重复使用液体火箭发动机 增强s型波纹管 疲劳寿命 液压成形
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Fatigue Life Prediction of Rolling Bearings Based on Modified SWT Mean Stress Correction 被引量:3
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作者 Aodi Yu Hong-Zhong Huang +2 位作者 Yan-Feng Li He Li Ying Zeng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第6期240-251,共12页
The existing engineering empirical life analysis models are not capable of considering the constitutive behavior of materials under contact loads;as a consequence,these methods may not be accurate to predict fatigue l... The existing engineering empirical life analysis models are not capable of considering the constitutive behavior of materials under contact loads;as a consequence,these methods may not be accurate to predict fatigue lives of roll-ing bearings.In addition,the contact stress of bearing in operation is cyclically pulsating,it also means that the bear-ing undergo non-symmetrical fatigue loadings.Since the mean stress has great effects on fatigue life,in this work,a novel fatigue life prediction model based on the modified SWT mean stress correction is proposed as a basis of which to estimate the fatigue life of rolling bearings,in which,takes sensitivity of materials and mean stress into account.A compensation factor is introduced to overcome the inaccurate predictions resulted from the Smith,Watson,and Topper(SWT)model that considers the mean stress effect and sensitivity while assuming the sensitivity coefficient of all materials to be 0.5.Moreover,the validation of the model is finalized by several practical experimental data and the comparison to the conventional SWT model.The results show the better performance of the proposed model,especially in the accuracy than the existing SWT model.This research will shed light on a new direction for predicting the fatigue life of rolling bearings. 展开更多
关键词 Rolling bearings Fatigue life prediction Modified sWT model mean stress correction
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A Novel Multiple Dependent State Sampling Plan Based on Time Truncated Life Tests Using Mean Lifetime 被引量:1
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作者 Pramote Charongrattanasakul Wimonmas Bamrungsetthapong Poom Kumam 《Computers, Materials & Continua》 SCIE EI 2022年第12期4611-4626,共16页
The design of a new adaptive version of the multiple dependent state(AMDS)sampling plan is presented based on the time truncated life test under the Weibull distribution.We achieved the proposed sampling plan by apply... The design of a new adaptive version of the multiple dependent state(AMDS)sampling plan is presented based on the time truncated life test under the Weibull distribution.We achieved the proposed sampling plan by applying the concept of the double sampling plan and existing multiple dependent state sampling plans.A warning sign for acceptance number was proposed to increase the probability of current lot acceptance.The optimal plan parameters were determined simultaneously with nonlinear optimization problems under the producer’s risk and consumer’s risk.A simulation study was presented to support the proposed sampling plan.A comparison between the proposed and existing sampling plans,namely multiple dependent state(MDS)sampling plans and a modified multiple dependent state(MMDS)sampling plan,was considered under the average sampling number and operating characteristic curve values.In addition,the use of two real datasets demonstrated the practicality and usefulness of the proposed sampling plan.The results indicated that the proposed plan is more flexible and efficient in terms of the average sample number compared to the existing MDS and MMDS sampling plans. 展开更多
关键词 Adaptive version of multiple dependent state sampling plan time truncated life test quality level weibull distribution mean lifetime
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Factors influencing quality of life in Chinese patients with dementia: a systematic review
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作者 Jin-Long Ma Bao-Jian Wei Yan-Mei Lang 《Aging Communications》 2023年第2期35-42,共8页
Background:Dementia is a group of nervous system diseases characterized by progressive cognitive decline,leading to a loss of self-care ability and a decline in well-being.This places a significant burden on the globa... Background:Dementia is a group of nervous system diseases characterized by progressive cognitive decline,leading to a loss of self-care ability and a decline in well-being.This places a significant burden on the global healthcare system,with Chinese patients accounting for approximately one-quarter of the world’s dementia cases.Therefore,it is crucial to identify factors that impact the quality of life(QOL)among elderly Chinese individuals with dementia.Method:To achieve this,we conducted a comprehensive search of several databases,including PubMed,Embase,Web of Science,the Cochrane Library,China National Knowledge Infrastructure,Wanfang Data,China VIP Database and China Biomedical Literature Database.We reviewed cross-sectional studies from the inception of these databases until March 27,2022.QOL outcomes were assessed using standardized scales in the studies included in this review.Results:The search yielded a total of 1,235 relevant articles,from which we finally included 21 cross-sectional studies and one longitudinal study after rigorous quality assessment.Among these,10 studies were classified as high quality,while 12 were classified as fair quality.Through our analysis,we identified 28 patient-rated QOL factors and 14 caregiver-rated QOL factors.These factors were categorized into three groups:patient,disease-related and caregiver.Factors commonly found to influence patient-rated QOL included age,education,marital status,depression,self-care ability,dementia severity,cognitive function,behavioral and psychological symptoms of dementia and caregiver burden.Similarly,factors commonly influencing caregiver-rated QOL included economic status,depression,self-care ability,dementia severity,cognitive function,behavioral and psychological symptoms of dementia and caregiving time.Conclusion:This review clarifies the factors that influence the QOL of Chinese individuals with dementia.When implementing interventions,it is crucial to consider the differences between patient-rated QOL and caregiver-proxy-rated QOL,as well as their respective influencing factors. 展开更多
关键词 DEMENTIA Alzheimer’s disease quality of life social support protective factors
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具有稚虫迁徙机制的S型自适应混沌蜉蝣算法
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作者 张恒齐 钱谦 《化工自动化及仪表》 CAS 2024年第2期262-273,共12页
针对蜉蝣优化算法(MA)全局搜索能力较弱,对子代优秀个体有效信息利用不够充分的缺点,以及在计算中后期易陷入局部收敛,进而影响优化效果的问题,提出一种具有稚虫迁徙机制的S型自适应混沌蜉蝣优化算法(S-AMA)。S-AMA算法首先采用Logisti... 针对蜉蝣优化算法(MA)全局搜索能力较弱,对子代优秀个体有效信息利用不够充分的缺点,以及在计算中后期易陷入局部收敛,进而影响优化效果的问题,提出一种具有稚虫迁徙机制的S型自适应混沌蜉蝣优化算法(S-AMA)。S-AMA算法首先采用Logistic混沌映射产生蜉蝣种群,增加算法初期种群的多样性;随后,将蜉蝣生命周期进行数学建模,并引入S型生命系数替换原有的重力惯性系数,动态调整算法探索能力和开发能力间的平衡性;最后,根据蜉蝣在缺氧环境下的种群活动,引入稚虫迁徙机制强化子代优秀个体摆脱局部最优的能力,进而更加充分地搜索最优解附近的区域,以增强算法的收敛精度。实验部分将S-AMA应用于标准函数测试集,并分别进行优化对比实验、Wilcoxon秩和检验。结果表明:与对比算法相比,S-AMA算法具有更好的寻优能力、收敛速度及鲁棒性。 展开更多
关键词 s型自适应混沌蜉蝣优化算法(s-AMA) 稚虫迁徙机制 混沌映射 s型生命系数 莱维飞行
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On the Weyl’s Lemma for Triharmonic Functions
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作者 ZHENG Run-jie ZENG Jia-min FANG Yi 《Chinese Quarterly Journal of Mathematics》 2024年第3期288-294,共7页
In this paper,by choosing some appropriate test functions,we prove the Weyl’s lemma for triharmonic functions based on the new type of mean value formulas.
关键词 Weyl’s lemma Harmonic functions Triharmonic functions Test functions mean value formulas
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Rags to Riches:Positive Psychological Attributes and Spiritual Factors Creating Meaning
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作者 Daniel P Knobel 《Psychology Research》 2020年第9期325-337,共13页
In mainstream media,the common perception is that“rags to riches”stories only consist of becoming“rich and famous”.This paper aims to reflect on the phenomenological experiences of 19 South Africans who significan... In mainstream media,the common perception is that“rags to riches”stories only consist of becoming“rich and famous”.This paper aims to reflect on the phenomenological experiences of 19 South Africans who significantly were able to move beyond their own significant low point experiences(imaginary:“rags”)into high point experiences(imaginary:“riches”).The presence of a meaningful experience indicates a turning point divide between low and high.Having the right positive psychological attributes supports the change required to move beyond your circumstances.The study explored the deeper internal psychological attributes within a person along with spiritual factors that could affect change in a person’s life to have an improved and fulfilling life.An existential-phenomenological-humanistic approach,from a positive psychological theoretical viewpoint,was used.The attributes were identified as themes through thematic analysis.The study found that meaning was the most prevalent feature in all respondents’lives to indicate a turn away from,sometimes intense,negative experiences.The presence of a positive mind-set(including positive attitude,self-thought,and self-talk)played a dominant role in affecting change,while the presence of faith and religious belief indicated the spiritual factors associated with change. 展开更多
关键词 CHANGE life experience meaning positive psychology psychological attributes sPIRITUAL
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