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A review of data-driven whole-life state of health prediction for lithium-ion batteries:Data preprocessing,aging characteristics,algorithms,and future challenges
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作者 Yanxin Xie Shunli Wang +3 位作者 Gexiang Zhang Paul Takyi-Aninakwa Carlos Fernandez Frede Blaabjerg 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期630-649,I0013,共21页
Lithium-ion batteries are the preferred green energy storage method and are equipped with intelligent battery management systems(BMSs)that efficiently manage the batteries.This not only ensures the safety performance ... Lithium-ion batteries are the preferred green energy storage method and are equipped with intelligent battery management systems(BMSs)that efficiently manage the batteries.This not only ensures the safety performance of the batteries but also significantly improves their efficiency and reduces their damage rate.Throughout their whole life cycle,lithium-ion batteries undergo aging and performance degradation due to diverse external environments and irregular degradation of internal materials.This degradation is reflected in the state of health(SOH)assessment.Therefore,this review offers the first comprehensive analysis of battery SOH estimation strategies across the entire lifecycle over the past five years,highlighting common research focuses rooted in data-driven methods.It delves into various dimensions such as dataset integration and preprocessing,health feature parameter extraction,and the construction of SOH estimation models.These approaches unearth hidden insights within data,addressing the inherent tension between computational complexity and estimation accuracy.To enha nce support for in-vehicle implementation,cloud computing,and the echelon technologies of battery recycling,remanufacturing,and reuse,as well as to offer insights into these technologies,a segmented management approach will be introduced in the future.This will encompass source domain data processing,multi-feature factor reconfiguration,hybrid drive modeling,parameter correction mechanisms,and fulltime health management.Based on the best SOH estimation outcomes,health strategies tailored to different stages can be devised in the future,leading to the establishment of a comprehensive SOH assessment framework.This will mitigate cross-domain distribution disparities and facilitate adaptation to a broader array of dynamic operation protocols.This article reviews the current research landscape from four perspectives and discusses the challenges that lie ahead.Researchers and practitioners can gain a comprehensive understanding of battery SOH estimation methods,offering valuable insights for the development of advanced battery management systems and embedded application research. 展开更多
关键词 Lithium-ion batteries Whole life cycle aging mechanism Data-driven approach State of health Battery management system
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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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Nowcasting and forecasting global aging and cancer burden:analysis of data from the GLOBOCAN and Global Burden of Disease Study
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作者 Lixi Li Tianhao Shan +1 位作者 Di Zhang Fei Ma 《Journal of the National Cancer Center》 2024年第3期223-232,共10页
Objective:To analyze the impact of global population aging on cancer epidemiology,with a focus on the incidence and mortality rates among individuals aged 60 years and above.Methods:We utilized open-source data,retrie... Objective:To analyze the impact of global population aging on cancer epidemiology,with a focus on the incidence and mortality rates among individuals aged 60 years and above.Methods:We utilized open-source data,retrieving population age estimates from the United Nations Population Division website.The GLOBOCAN 2020 database provided estimates for cancer cases and deaths in 2020 and 2040,while the Global Burden of Disease 2019 database supplied estimates of new cancer cases worldwide from 2000 to 2019.Inclusion criteria considered individuals aged 60 years and over,focusing on the top five deadliest cancers.The cohort-component method was employed for population prediction,with age-specific incidence and mortality rates estimated for 2020 used to forecast the cancer burden.Results:In 2021,the global population aged over 60 years accounted for 13.7%,with Europe/North America and Australia/New Zealand having the highest proportions.The older population is predicted to reach 19.2%by 2040.In 2020,of the 19.3 million new cancer cases worldwide,64%occurred in individuals aged 60 and above,contributing to 71.3%of cancer-related deaths.The five most common cancer sites were the lung,colorectum,prostate,breast,and stomach.Cancer incidence and deaths are projected to rise significantly among older indi-viduals,reaching 20.7 million new cases and 12.7 million deaths by 2040.Older age,tobacco use,dietary factors,alcohol consumption,and high body mass index(BMI)were identified as major risk factors for various cancers in this demographic.Conclusions:This study reveals a significant rise in cancer incidence and mortality among the elderly due to global population aging.The urgency for targeted interventions in cancer prevention,screening,and treatment for older individuals is emphasized.Despite acknowledged limitations,these findings contribute valuable insights to inform strategies for managing cancer in the elderly amidst evolving demographic trends. 展开更多
关键词 Global aging Cancer burden Public health Disability-adjusted life years
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Experimental study of water aging on asphalt during service life of pavements 被引量:9
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作者 卞凤兰 赵永利 +1 位作者 黄晓明 王真 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期618-621,共4页
In order to further simulate the real condition of pavements during the service life,moisture is considered in long-term aging tests based on the existing researches about thermal aging and oxidation aging of asphalt.... In order to further simulate the real condition of pavements during the service life,moisture is considered in long-term aging tests based on the existing researches about thermal aging and oxidation aging of asphalt.Water is injected into the pressure aging vessel(PAV)to simulate the aging process during the service life.The performance-based strategic highway research program(SHRP)parameters G/sinδ and S(t)are adopted to evaluate the high-temperature properties and low-temperature properties of the aged asphalt,respectively.The Thailand 90# asphalt,the modified Thailand 90# asphalt and the Shell 70# asphalt are used in the test.It is found that the moisture has a significant influence on parameter G/sinδ when combined with heat and oxygen,so water aging makes high-temperature performance decay more seriously.But the low-temperature performance does not change remarkably after water aging.Since the influences of temperature,oxygen and water are taken into account in the PAV test,the accuracy of asphalt aging tests can be improved and the long-term aging process of asphalt pavement can be exactly simulated. 展开更多
关键词 ASPHALT water aging SHRP method service life
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T6态热挤压Al-5Cu-0.8Mg-0.15Zr-0.2Sc-0.5Ag合金的低周疲劳行为
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作者 王莹 陈立佳 +2 位作者 周舸 张浩宇 张思倩 《沈阳工业大学学报》 CAS 北大核心 2024年第1期77-81,共5页
为了揭示经过T6处理的热挤压Al-5Cu-0.8Mg-0.15Zr-0.2Sc-0.5Ag合金在不同温度下的低周疲劳变形与断裂行为,对T6态热挤压合金进行了室温和200℃条件下的低周疲劳实验。结果表明:在室温和200℃下合金塑性应变幅与载荷反向周次之间服从Coff... 为了揭示经过T6处理的热挤压Al-5Cu-0.8Mg-0.15Zr-0.2Sc-0.5Ag合金在不同温度下的低周疲劳变形与断裂行为,对T6态热挤压合金进行了室温和200℃条件下的低周疲劳实验。结果表明:在室温和200℃下合金塑性应变幅与载荷反向周次之间服从Coffin-Manson公式,而弹性应变幅与载荷反向周次之间服从Basquin公式;合金在室温和200℃下低周疲劳变形时,在较低外加总应变幅下疲劳变形机制主要为平面滑移,而在较高外加总应变幅下疲劳变形机制主要为波状滑移;室温和200℃下合金的疲劳裂纹均萌生于疲劳试样表面并以穿晶方式扩展。 展开更多
关键词 AL-CU-MG-ag合金 T6处理 低周疲劳 循环硬化 循环稳定 疲劳寿命 变形机制 疲劳断裂
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Storage life prediction under pre-strained thermally-accelerated aging of HTPB coating using the change of crosslinking density 被引量:2
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作者 Yong-qiang Du Jian Zheng Gui-bo Yu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第4期1387-1394,共8页
In order to predict the storage life of a certain type of HTPB(hydroyl-terminated polybutadiene)coating at 25℃ and analyze the influence of pre-strain on the storage life,the accelerated aging tests of HTPB coating a... In order to predict the storage life of a certain type of HTPB(hydroyl-terminated polybutadiene)coating at 25℃ and analyze the influence of pre-strain on the storage life,the accelerated aging tests of HTPB coating at 40℃,50℃,60℃,70℃ with the pre-strain of 0%,3%,6%,9%,respectively were carried out.The variation regularity of the change of crosslinking density was analyzed and the aging model of HTPB coating under pre-strained thermally-accelerated aging was proposed.The storage life of HTPB coating at 25℃ was estimated by using the Berthelot equation as the end point of the aging life with a 30% decrease in maximum elongation.The results showed that the change of crosslinking density of HTPB coating increased with the increase of aging temperature and aging time,and decreased with the increase of pre-strain.Under 0% prestrain,the relationship between the change of crosslinking density of HTPB coating and the aging time can be described by the logarithmic model with the confidence probability greater than 99%.The stress relaxation phenomenon existed under 3%,6%and 9%pre-strained aging.The aging model considering chemical aging and pre-strain was established with the confidence probability greater than 90%.The storage life of HTPB coating was 15.2935 years at 25C under 0% prestrain,which was reduced by 13.9007%,75.6949% and 89.7859% under 3%,6% and 9% pre-strain,respectively.The existence of pre-strain has a serious impact on the storage life of HTPB coating,therefore,the pre-strain should be avoided as much as possible during the actual storage. 展开更多
关键词 HTPB coating Crosslinking density aging model Storage life prediction Berthelot
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The Role of Well-Being, Spirituality, and Religiosity for Successful Aging in Late Life: A Brief Review 被引量:1
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作者 Dimitrios Papadopoulos 《Advances in Aging Research》 2020年第2期23-31,共9页
Much research has highlighted the aging process as a global, multi-faceted issue, focusing on modifiable factors that can improve physical health and psychosocial well-being in late life. This is particularly true for... Much research has highlighted the aging process as a global, multi-faceted issue, focusing on modifiable factors that can improve physical health and psychosocial well-being in late life. This is particularly true for both developed and developing countries, which are likely to face long-term issues in health and psychosocial care as the aging of their population increases. Within the theoretical framework of successful aging and developmental psychology, this paper aims to review recent advances in our knowledge of middle and late-life well-being in order to better understand the role of well-being and spirituality/religiosity across adulthood. The results of the selected studies allow us to conclude that subjective, hedonic, and eudemonic well-being and religious practices are significant determinants shaping the overall psychological well-being, life satisfaction, and social functioning of the older population. Limitations and implications of the study will also be discussed. 展开更多
关键词 aging ADULTHOOD WELL-BEING Religiosity life SATISFACTION
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Esophageal cancer global burden profiles, trends, and contributors
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作者 Yi Teng Changfa Xia +9 位作者 Maomao Cao Fan Yang Xinxin Yan Siyi He Mengdi Cao Shaoli Zhang Qianru Li Nuopei Tan Jiachen Wang Wanqing Chen 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第8期656-666,共11页
Objective:This study aimed to provide a comprehensive overview of the global burden of esophageal cancer(EC)and determine the temporal trends and factors influencing changes in the global burden.Methods:The latest inc... Objective:This study aimed to provide a comprehensive overview of the global burden of esophageal cancer(EC)and determine the temporal trends and factors influencing changes in the global burden.Methods:The latest incidence and mortality data for EC worldwide were obtained from GLOBALCAN 2022.The mortality and disability-adjusted life years(DALYs)rates for EC from 1990±2019 were sourced from the 2019 Global Burden of Diseases.Trends in EC mortality and DALYs attributable to 11 risk factors or clusters of risk were analyzed using the joinpoint regression model.The trends in age-related EC burden were assessed using a decomposition approach.Results:An estimated 511,054 new cases of EC were diagnosed in 2022 with 445,391 deaths worldwide.Approximately 75%of cases and deaths occurred in Asia.Nearly 50%of global EC deaths and DALYs were attributed to tobacco use in men in 2019,while 20%were attributed to high body mass index(BMI)in women.From 1990±2019,EC deaths and DALYs attributable to almost all risk factors had declining trends,while EC deaths and DALYs attributed to high BMI in men had upward trends.The age-related EC burden exhibited an upward trend driven by population growth and aging,which contributed to 307.4 thousand deaths and 7.2 million DALYs due to EC.Conclusions:The EC burden remains substantial worldwide.Effective tobacco and obesity control measures are critical for addressing the risk-attributable burden of EC.Population growth and aging pose challenges for EC prevention and control efforts. 展开更多
关键词 Esophageal cancer INCIDENCE MORTALITY disability-adjusted life years risk factors aging TRENDS
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Application of time-temperature superposition method in thermal aging life prediction of shipboard cables
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作者 邓文东 CHEN Yi-yuan 《Journal of Chongqing University》 CAS 2014年第4期142-150,共9页
The life of shipboard cables will decrease due to the complex aging processes. In terms of the safety perspective, remaining life prediction of the cable is essential to maintain a reliable operation. In this paper, f... The life of shipboard cables will decrease due to the complex aging processes. In terms of the safety perspective, remaining life prediction of the cable is essential to maintain a reliable operation. In this paper, firstly, based on Arrhenius equation, residual life of new styrene-butadiene cable is calculated; result indicates that the degradation rate which changes with time is proportional to thermal temperature. Then second order dynamic model is adopted into the residual life prediction, combined with the time-temperature superposition method(TTSP), and a new residual life model is proposed. According to the accelerated thermal aging experiment data and Arrhenius equation, TTSP method demonstrates to be an efficient way for life prediction, and life at normal temperature can be estimated by this model. In order to monitor the state of styrene-butadiene cable more accurately, an improved residual life model based on equivalent environment temperature of cable is proposed, and life of cable under real operation is analyzed. Result indicates that this model is credible and reliable, and it provides an important theoretical base for residual life of cables. 展开更多
关键词 insulated cable thermal aging Arrhenius equation TTSP residual life
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Health, Aging and Quality of Life: An Evaluation of Experience in Family Health Unit through Popular Education
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作者 Cristina Katya Torres Teixeira Mendes Fabia Barbosa de Andrade +4 位作者 Danielle Nóbrega de Castro Maria do Socorro Feitosa Alves Gilson de Vasconcelos Torres Maria Adelaide Paredes Moreira Antonia Oliveira Silva 《Health》 2014年第15期1959-1963,共5页
This study aims to assess the implementation of the Health, Aging and Quality of Life. The specific objectives were executed by conducting activities with the elderly through generative themes with an emphasis on heal... This study aims to assess the implementation of the Health, Aging and Quality of Life. The specific objectives were executed by conducting activities with the elderly through generative themes with an emphasis on health, aging and quality of life;evaluation of the experience of older people in Unity Family Health with Popular Education;analyzing the evolution of indicators of health and quality of life of elderly patients after two years and ascertaining the effectiveness of Popular Education in the elderly group in the Family Health Unit. This is an exploratory study approved by the Ethics and Research Committee UFPB/CCS, number 0598/08 held on Primary Health Care. The project consists of two lines of integrated activities: Group Active Ageing (GEA), which brings together seniors for addressing issues related to healthy aging and the Multidimensional Health Assessment and Quality of Life through the WHOQOL-BREF. The activities were built in fortnightly meetings from the dialogue where experiences are shared and collective needs. Thus, relevant topics were suggested for the group: guidelines on physical activity, nutrition, chronic disease prevention, self-esteem, among others, and group dynamics as body stretching, stretching exercises, respiratory, metabolic and relaxation. The observed results are the very satisfactions group, reported through testimonies and translated by the enthusiasm and diligence in participation. This project promoted a better bio-psycho-social development of the elderly, reinforcing its identity by promoting and facilitating the expression of their potential positive and arousing them to a better future life prospects and community socialization feelings. 展开更多
关键词 HEALTH aging QUALITY of life
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The Direction of Research on Active Aging and Healthy Life Expectancy in Japan
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作者 Atsuko Tokushige Daiji Araki +2 位作者 Miyuki Suzuki Yukie Iwasaki Mizuho Ozawa 《Open Journal of Nursing》 2014年第7期475-482,共8页
In Japan, 18.1% of the population known as baby-boomers will become the late-stage elderly in 2025, thereby needing a foundation to support this change. The Japanese Ministry of Health, Labour and Welfare is promoting... In Japan, 18.1% of the population known as baby-boomers will become the late-stage elderly in 2025, thereby needing a foundation to support this change. The Japanese Ministry of Health, Labour and Welfare is promoting the development of a regional comprehensive system allowing the elderly to continue living in their familiar surroundings. However, a care shortage is inevitable unless elders are able to age in good health, regardless of the system’s level of enhancement. This study aims to review the literature on active aging, clarify trends in clinical operations undertakings and research in Japan, and consider relevant research issues. After combining the search results of “active aging” and “healthy life expectancy,” we used a text mining technique to analyze the abstracts of 120 original articles and 213 reviews, commentaries, and features. Eight categories were extracted from the original articles: health statistics, gender, age, etc. From the reviews, commentaries, and features, 16 categories were extracted: orientation, disease, and living, etc. Cerebrovascular disease and osteoporosis were the most common diseases covered in the original articles;there has been a substantial amount of research on “active aging” and “healthy life expectancy” because they can easily lead to being bedridden and to a decrease in QOL. In the reviews, commentaries, and features, lifestyle-related diseases and menopause rather than cerebrovascular disease and osteoporosis, were extracted. The categorical differences found in the original articles may be due to the possibility that Japanese researchers are publishing their research abroad rather than in Japan or they submit research on topics that are guaranteed to be published at home or abroad. Little research has been conducted using the terms, “active aging” and “healthy life expectancy,” evidenced by the small number of studies generated. Preparations for 2025 will require an increase in the number of studies from the perspective of “active aging” and “healthy life expectancy.” 展开更多
关键词 Active aging HEALTHY life EXPECTANCY TEXT MINING
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Aging and Life Management System of Reactor Pressure Vessel
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作者 Ya-jin Liu Jiang Guo Kai-kai Gu 《World Journal of Nuclear Science and Technology》 2011年第2期21-25,共5页
Reactor pressure vessel (RPV), the only key component that can not be replaced in nuclear power plants (NPPs), is the main barrier against the radioactive leakage. The lifetime of NPPs is dependent heavily on the life... Reactor pressure vessel (RPV), the only key component that can not be replaced in nuclear power plants (NPPs), is the main barrier against the radioactive leakage. The lifetime of NPPs is dependent heavily on the life of RPV, and thus, the aging and life research on a RPV is a key factor in determining the life extension of NPPs. The purpose of this paper is to introduce an aging and life management system for an operating RPV which can be used as a reference of the lifetime extension. In order to realize the objective, an aging and life management system was developed. It is an comprehensive knowledge management system that integrates decentralized information and serves as a valuable data center. Based on the storage and management of RPV state information and operation data, this system provides real-time monitoring of important operating parameters, evaluation of irradiation embrittlement, and RPV aging assessment. Therefore, it is anticipated that the developed system can be used as an efficient tool for aging and life estimation of RPV. 展开更多
关键词 REACTOR Pressure VESSEL NUCLEAR Power PLANTS aging and life Management
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Master Curve Method of Cumulative Damage for Prediction of Service Life
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作者 沈庭芳 赵伯华 《Journal of Beijing Institute of Technology》 EI CAS 1999年第1期109-113,共5页
Aim To study the theory and method for the prediction of service life of solid rocket propellant grain. Methods With the aid of discontiguous diagnostic technology and method of accumulated damage using accelerated... Aim To study the theory and method for the prediction of service life of solid rocket propellant grain. Methods With the aid of discontiguous diagnostic technology and method of accumulated damage using accelerated aging or heat air oven, the aging isotherms for void content versus aging time were determined. According to the principle of time temperature equivalence the viscoelastic master curve for the prediction of service life were obtained. Results and Conclusion The service life of HMX CMDB solid rocket propellant grain were obtained. Because the critical storage life is measured, the accuracy of predicting the service life of the grain has been increased greatly. 展开更多
关键词 void content thermal aging cumulative damage service life
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Aging men-Challenges ahead 被引量:10
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作者 Bruno Lunenfeld 《Asian Journal of Andrology》 SCIE CAS CSCD 2001年第3期161-168,共8页
The prolongation of life expectancy and the drastic reduction of fertility rate are the primary cause of an agingworld. It is projected that the elderly (above 65) will increase within the next 25 years by 82% , where... The prolongation of life expectancy and the drastic reduction of fertility rate are the primary cause of an agingworld. It is projected that the elderly (above 65) will increase within the next 25 years by 82% , whereas the new bornonly by 3% . Despite the enormous medical progress during the past few decades, the last years of life are still accom-panied by increasing ill health and disability. The ability to maintain active and independent living for as long as possi-ble is a crucial factor for aging in health and dignity. Therefore, the promotion of healthy aging and the prevention ofdisability in men, must assume a central role in medical research and medical practice as well as in the formulation ofnational health and social policies. Effective programs promoting health and aging will ensure a more efficient use ofhealth and social services and improve the quality of life in older persons by enabling them to remain independent andproductive. The most important and drastic gender differences in aging are related to organs and or systems dependantor influenced by reproductive hormones. In distinction to the course of reproductive aging in women, with the rapid de-cline in sex hormones and expressed by the cessation of menses, aging men experience a slow and continuous decline ofhormones. This decline in endocrine function involves; A decrease of testosterone, dehydroepiandrosterone (DHEA),oestrogens, thyroid stimulating hormone (TSH), growth hormone (GH), insulin-like growth factor-1 (IGF-1), andmelatonin. This decrease is concomitant with an increase of LH and FSH. In addition sex hormone binding globulin's(SHBG) increase with age resulting in further lowering the concentrations of free biologically active androgens. Inter-ventions such as hormone replacement therapy may prevent, delay or alleviate the debilitating conditions which may re-sult from secondary partial endocrine deficiency. Primary and secondary preventive strategies such as the promotion of asafe environment, healthy lifestyle including proper nutrition, appropriate exercise, avoidance of smoking, avoidanceof drug and alcohol abuses, if done effectively, should result in a significant reduction of the health and social costs,reduce pain and suffering, increase the quality of life of the elderly and enable them to remain productive and contributeto the well-being of society. In light of this, public awareness of medical knowledge needs to be increased and basic,clinical, socio-economic and epidemiological research intensified. (Asian J Androl 2001 Sep; 3; 161 - 168) 展开更多
关键词 aging life expectancy health expectancy FERTILITY HRT(hormone replacement therapy) quality of life preventive strategies
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Aging Mechanism and Life Estimation of Photovoltaic Inverter DC-link Capacitors in Alternating Humid and Thermal Environment
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作者 Quanyi Gao Shuaibing Li +2 位作者 Yi Cui Yongqiang Kang Haiying Dong 《Chinese Journal of Electrical Engineering》 EI CSCD 2024年第1期48-62,共15页
DC-link capacitors play a vital role in managing ripple voltage and current in converters and various devices.This study focuses on exploring the aging characteristics of DC-link capacitors in alternating humid and th... DC-link capacitors play a vital role in managing ripple voltage and current in converters and various devices.This study focuses on exploring the aging characteristics of DC-link capacitors in alternating humid and thermal environments aligned with the operational conditions in photovoltaic and wind power applications.Adhering to relevant power equipment standards,we designed a 24-h alternating humid and thermal aging environment tailored to the requirements of DC-link capacitors.An aging test platform is established,and 20 widely used metallized polypropylene film capacitors are selected for evaluation.Parameters such as the capacitance,equivalent series resistance(ESR),and phase angle are assessed during aging,as well as the onset time and extent of aging at various intervals.This study focuses on the aging mechanisms,analyzing electrode corrosion,the self-healing process,and dielectric aging.Fitting the aging characteristics enabled us to calculate the lifespan of the capacitor and predict it under different degrees of capacitance decay.The results show that under alternating humid and thermal conditions,capacitance attenuation and ESR increase exhibit exponential nonlinearity,influenced by factors such as the oxidation and self-healing of capacitive metal electrodes,dielectric main-chain fracture,and crystal transformation.This study underscores the pivotal role of encapsulation in determining the aging decay time. 展开更多
关键词 DC-link capacitors aging mechanism life prediction metallized film capacitors
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A Study of Estimating the Safe Storage Life, Self-accelerating Decomposition Temperature and Critical Temperature of Thermal Explosion of Double-base Propellant Using Isothermal and Non-isothermal Decomposition Behaviours 被引量:1
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作者 Feng Qi ZHAO Hong Xu GAO +2 位作者 Rong Zu HU Gui E LU Jin Yong JIANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第5期667-670,共4页
A method of estimating the safe storage life (τ), self-accelerating decomposition temperature (TsADT) and critical temperature of thermal explosion (Tb) of double-base propellant using isothermal and non-isothe... A method of estimating the safe storage life (τ), self-accelerating decomposition temperature (TsADT) and critical temperature of thermal explosion (Tb) of double-base propellant using isothermal and non-isothermal decomposition behaviours is presented. For double-base propellant composed of 56±1wt% of nitrocellulose (NC), 27±0.5wt% of nitroglycerine (NG), 8.15±0.15wt% of dinitrotoluene (DNT), 2.5±0.1wt% of methyl centralite, 5.0±0.15wt% of catalyst and 1.0±0.1wt% of other, the values of r of 49.4 years at 40℃, of TSAOT of 151.35℃ and of Tb of 163.01℃ were obtained. 展开更多
关键词 Safe storage life self-accelerating decomposition temperature critical temperature of thermal explosion double-base propellant thermal accelerated aging test DSC kinetic parameters.
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Asset Life Cycle Management in Finnish Water Utilities
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作者 Riikka P. Rajala Jarmo J. Hukka 《Journal of Water Resource and Protection》 2018年第6期587-595,共9页
The aim of this paper is to improve the water industry asset life cycle management framework towards more resilient water services in Finland. This paper is based on a literature study and a web-based semi-structured ... The aim of this paper is to improve the water industry asset life cycle management framework towards more resilient water services in Finland. This paper is based on a literature study and a web-based semi-structured thematic interview, in which the Finnish water utility managers identified the current status of their utilities’ asset management. The water services professionals are extremely worried that, by and large, water and sewage networks are still deteriorating, although the networks are nowadays rehabilitated more systematically. The survey reveals that although most of the surveyed utilities have adopted several processes and sub-processes of asset management, and a few utilities are even using some asset management guides, as a whole a strategic approach to and a comprehensive framework for optimized management of physical assets are not practiced. Therefore the development and introduction of specific asset management guidelines should be considered. In order to support successful usage of the asset management framework, the basic concepts and principles of engineering asset management should be included in educational and professional development programs, in particular at the university level. 展开更多
关键词 FINNISH WATER UTILITIES aging Infrastructure ASSET life Cycle MANagEMENT Framework Regulation and ENFORCEMENT
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Observation on the quality of life before and after the injection of antiangiogenic drug in the vitreous cavity of patients with wet age-related macular degeneration 被引量:1
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作者 Dan-Dan Wang Pei-Ying Xu +2 位作者 Tian-Yu Wang Xiao-Xia Chen Qing Peng 《Chinese Nursing Research》 CAS 2015年第1期35-39,共5页
Objective: To explore the vision-related quality of life ( VRQL) before and after the injection of antiangiogenic drug into the vitreous cavity of patients with wet age-related macular degeneration ( AMD) . Methods: T... Objective: To explore the vision-related quality of life ( VRQL) before and after the injection of antiangiogenic drug into the vitreous cavity of patients with wet age-related macular degeneration ( AMD) . Methods: The 2000 edition of the Visual Functioning Questionnaire 25 that was issued by the Na-tional Eye Institute was applied, and the VRQL evaluation was conducted on the initially diagnosed patients with wet-AMD before and after the injection of ranibizumab into the vitreous cavity. Results: Among the wet-AMD patients, patients with better distance visual acuity before the in-travitreal injection had a lower VFQ-25 score. After the vitreous cavity injection, the VFQ-25 questionnaire score was related to patient care and education from the doctors and nurses; specific-ally, the better the nursing, the higher the score. Conclusions: Before the vitreous cavity injection, the degree of distance visual acuity is an im-portant factor affecting the VRQL of wet-AMD patients. In addition, patient care and education from the doctors and nurses toward patients during the pre-, intra-and post-operation of the intrav-itreal injection are also important factors affecting the VRQL. 展开更多
关键词 age-related macular degeneration Intravitreal injection Quality of life
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Daily Life and Planning for the Future of Ageing People with Down Syndrome: Results from a National Study on Caregivers
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作者 Venusia Covelli Erika Guastafierro Matilde Leonardi 《Advances in Aging Research》 2020年第6期95-115,共21页
<strong>Background</strong>:<span> </span><span>Limited research concerns the study of continuity in the future of the physical and social status of elderly people with DS that is when pe... <strong>Background</strong>:<span> </span><span>Limited research concerns the study of continuity in the future of the physical and social status of elderly people with DS that is when people who take care of them will not be there anymore (“<i></i></span><i><i><span>after</span></i><span> </span><i><span>we</span></i><span> </span><i><span>have</span></i><span> </span><i><span>gone</span></i></i><span>”). </span><b><span>Objective</span></b><b><span>:</span></b><span> From a biopsychosocial perspective, to investigate the daily life of ageing people with Down Syndrome over 45 years old in order to identify the most important issues in better planning for their future. </span><b><span>Methods</span></b><b><span>:</span></b><span> A cross-sectional Italian national study was carried out. An <i></i></span><i><i><span>ad</span></i><span> </span><i><span>hoc</span></i></i><span> questionnaire was administered to formal and informal caregivers of aging people with Down Syndrome. </span><b><span>Results</span></b><b><span>:</span></b><span> 136 family members and health professionals were involved. Most of </span><span>the </span><span>people with Down Syndrome live at home, attend a daily center and do many activities. Most of them had never worked and she/he is not at all autonomous. 25% of caregivers declared that, nowadays, there is not planning for the future, and 30.9% of participants who planned their future collected information when it occurred (e.g. when the parents pass away). </span><b><span>Conclusions</span></b><b><span>:</span></b><span> </span><span>The a</span><span>ging of people with DS requires attention to the planning of their future. In order to better plan, it is necessary to avoid programming </span><span>“</span><span>in emergency</span><span>”</span><span>, but for time, keeping in mind of the activities developed by the people, their abilities and all of the elements that have allowed them to live well up to a point of their life.</span> 展开更多
关键词 Down Syndrome Trisomy 21 Future life ageing ELDERLY Biopsychosocial Approach
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Performance Survey of PVC Insulation of LC/Gecamines Electrical Cables Subjected to Ageing and Its Life Span Evaluation
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作者 Chungu Mwana Mwamba Yannick Michael Kabangu Ngoie +4 位作者 Muliangala Mbalaba Francis Kasambay Mutangala Francis Katamea Mwanvua Mavé Twite Kabamba Edmond Lukozi Mufaume Donatien 《World Journal of Engineering and Technology》 2022年第4期728-737,共10页
Considering the insulators ageing in a mixture of PVC and dye, set following operating conditions and time to ensure proper operation and perfect safety of industrial installations using insulated conductors. The resu... Considering the insulators ageing in a mixture of PVC and dye, set following operating conditions and time to ensure proper operation and perfect safety of industrial installations using insulated conductors. The results showed that the insulation carried out by the L.C main office was a good quality (on thermal aspect), because the resistance of the insulation is so high (i.e. 3940 Mega Ohms under normal conditions). The results showed a lifespan of 50 years at a temperature of 40°C (close to ambient temperature), plus minus 33 years at a temperature of 70°C;plus minus 22 years at a temperature of 100°C and 12 years at a temperature of 160°C. Furthermore, information on chemical attack, the results showed that PVC cables have poor resistance to sulfuric acid attack (having a pH of 1.5 and a density of 1.84 g/cm<sup>3</sup>). LC/Gecamines is able to produce locally a good quality of electrical cables. 展开更多
关键词 PVC PERFORMANCE Thermal ageing Chemical Resistance Cable life Span
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