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Effects of air damping on quality factors of different probes in tapping mode atomic force microscopy
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作者 Yu Zeng Guo-Lin Liu +1 位作者 Jin-Hao Liu Zheng Wei 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期506-519,共14页
The AFM probe in tapping mode is a continuous process of energy dissipation,from moving away from to intermittent contact with the sample surfaces.At present,studies regarding the energy dissipation mechanism of this ... The AFM probe in tapping mode is a continuous process of energy dissipation,from moving away from to intermittent contact with the sample surfaces.At present,studies regarding the energy dissipation mechanism of this continuous process have only been reported sporadically,and there are no systematic explanations or experimental verifications of the energy dissipation mechanism in each stage of the continuous process.The quality factors can be used to characterize the energy dissipation in TM-AFM systems.In this study,the vibration model of the microcantilever beam was established,coupling the vibration and damping effects of the microcantilever beam.The quality factor of the vibrating microcantilever beam under damping was derived,and the air viscous damping when the probe is away from the sample and the air squeeze film damping when the probe is close to the sample were calculated.In addition,the mechanism of the damping effects of different shapes of probes at different tip–sample distances was analyzed.The accuracy of the theoretical simplified model was verified using both experimental and simulation methods.A clearer understanding of the kinetic characteristics and damping mechanism of the TM-AFM was achieved by examining the air damping dissipation mechanism of AFM probes in the tapping mode,which was very important for improving both the quality factor and the imaging quality of the TM-AFM system.This study’s research findings also provided theoretical references and experimental methods for the future study of the energy dissipation mechanism of micro-nano-electromechanical systems. 展开更多
关键词 TM-AFM quality factors air viscous damping air squeeze film damping
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Dynamic Development Characteristics and Driving Factors of High Quality Development Level in China’s Five Major Urban Agglomerations
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作者 ZOU Weiyong XU Lingli 《Chinese Geographical Science》 SCIE CSCD 2024年第5期777-790,共14页
High-quality development is the primary task of comprehensively building a socialist,modern country,as well as the primary task of building urban agglomerations in China.Based on the five development concepts,this pap... High-quality development is the primary task of comprehensively building a socialist,modern country,as well as the primary task of building urban agglomerations in China.Based on the five development concepts,this paper used the entropy method to measure the High Quality Development Index(HQDI)of the five major urban agglomerations.The results showed that the HQDI of the five major urban agglomerations shows a fluctuating upward trend.First,using the Dagum Gini coefficient to explore the sources of HQDI development differences in urban agglomerations,we found that the main source of HQDI differences in urban agglomerations was inter-regional differences,while intra-regional differences were not important.Second,kernel density estimation was used to test the dynamic evolution trend of HQDI within urban agglomerations.There was a polarisation phenomenon in the HQDI of urban agglomerations,such as the Pearl River Delta urban agglomeration and the Chengdu-Chongqing urban agglomeration.But overall,the degree of imbalance had decreased.Third,using geographic detectors to examine the driving factors of HQDI in urban agglomerations,we found that the main driving forces for improving HQDI in urban agglomerations were economic growth,artificial intelligence technology and fiscal decentralisation.All the interaction factors had greater explanatory power for the spatial differentiation of HQDI,which can be divided into two types:two-factor improvement and non-linear improvement.This study is conducive to improving and enriching the theoretical system for evaluating the high quality development of urban agglomerations,and provides policy references for promoting the high quality development of urban agglomerations. 展开更多
关键词 urban agglomeration High quality Development Index(HQDI) spatio-temporal evolution driving factors
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A Problem Not to Be Ignored: The Influencing Factors of Mobile Phone Addiction and Its Influence on Sleep Quality
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作者 Zihan Ji Lian Zhou 《Health》 2024年第5期459-469,共11页
Background and Objective: With the popularity and widespread use of mobile phones, the effects of mobile phone dependence and addiction on individuals’ physical and mental health have attracted more and more attentio... Background and Objective: With the popularity and widespread use of mobile phones, the effects of mobile phone dependence and addiction on individuals’ physical and mental health have attracted more and more attention. The present study aims to analyze the current state of mobile phone addiction and its impact on sleep quality within the population, while also exploring the influence of related factors on sleep quality. Ultimately, this research will provide a scientific foundation for targeted intervention measures and strategies. Methods: A total of 253 permanent residents in Nanjing were randomly selected as study subjects. The Mobile Phone Addiction Index (MPAI) and Pittsburgh Sleep Quality Index (PSQI) were used to evaluate the degree of smartphone addiction and sleep quality of the study subjects. Body mass index (BMI) was measured according to standardized procedures. Independent sample t-test, Chi-square test, rank sum test and multiple linear regression were used to analyze the correlation between mobile phone addiction and sleep quality, and P Results: 117 people (46.2%) were addicted to mobile phones. Chi-square test showed that the rate of mobile phone addiction in drinking group was significantly higher than that in non-drinking group (P P P P P P P P P P Conclusion: Mobile phone addiction may lead to shorter sleep duration and reduce sleep efficiency. The withdrawal of mobile phone addiction may have a negative impact on sleep quality. According to the characteristics of the population, appropriate comprehensive intervention measures should be taken to build an effective evaluation system, so as to reduce the impact of mobile phone addiction and withdrawal problems on sleep and improve sleep quality. 展开更多
关键词 Mobile Phone Addiction Influencing factors WITHDRAWAL Sleep quality
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Ecological environmental quality evaluation and driving factor analysis of the Lijiang River Basin,based on Google Earth Engine
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作者 WEI Xi YANG Dazhi +2 位作者 CAI Xiangwen SHAO Ya TANG Xiangling 《中国生态农业学报(中英文)》 CAS CSCD 北大核心 2024年第9期1592-1608,共17页
For regional ecological management,it is important to evaluate the quality of ecosystems and analyze the underlying causes of ecological changes.Using the Google Earth Engine(GEE)platform,the remote sensing ecological... For regional ecological management,it is important to evaluate the quality of ecosystems and analyze the underlying causes of ecological changes.Using the Google Earth Engine(GEE)platform,the remote sensing ecological index(RSEI)was calculated for the Lijiang River Basin in Guangxi Zhuang Autonomous Region for 1991,2001,2011,and 2021.Spatial autocorrelation analysis was employed to investigate spatiotemporal variations in the ecological environmental quality of the Lijiang River Basin.Furthermore,geographic detectors were used to quantitatively analyze influencing factors and their interaction effects on ecological environmental quality.The results verified that:1)From 1991 to 2021,the ecological environmental quality of the Lijiang River Basin demonstrated significant improvement.The area with good and excellent ecological environmental quality in proportion increased by 19.69%(3406.57 km^(2)),while the area with fair and poor ecological environmental quality in proportion decreased by 10.76%(1860.36 km^(2)).2)Spatially,the ecological environmental quality of the Lijiang River Basin exhibited a pattern of low quality in the central region and high quality in the periphery.Specifically,poor ecological environmental quality characterized the Guilin urban area,Pingle County,and Lingchuan County.3)From 1991 to 2021,a significant positive spatial correlation was observed in ecological environmental quality of the Lijiang River Basin.Areas with high-high agglomeration were predominantly forests and grasslands,indicating good ecological environmental quality,whereas areas with low-low agglomeration were dominated by cultivated land and construction land,indicating poor ecological environmental quality.4)Annual average precipitation and temperature exerted the most significant influence on the ecological environmental quality of the basin,and their interactions with other factors had the great influence.This study aimed to enhance understanding of the evolution of the ecological environment in the Lijiang River Basin of Guangxi Zhuang Autonomous Region and provide scientific guidance for decision-making and management related to ecology in the region. 展开更多
关键词 Ecological environmental quality Remote sensing ecological index Driving factor Google Earth Engine Lijiang River Basin
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Research on the Impact of China’s Foreign Trade Technology Spillover on Green Total Factor Productivity of Countries Along the“Belt and Road”:Based on the Institutional Quality Threshold Effect
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作者 Li Chai Longnan Ma Lingwei Meng 《Proceedings of Business and Economic Studies》 2024年第2期120-125,共6页
China’s growing trade with countries along the“Belt and Road”Initiative is accompanied by a focus on green development.Based on the panel data from 2007 to 2018,this paper establishes a threshold regression model t... China’s growing trade with countries along the“Belt and Road”Initiative is accompanied by a focus on green development.Based on the panel data from 2007 to 2018,this paper establishes a threshold regression model to empirically analyze the institutional quality threshold effect of China’s foreign trade technology spillover on the GTFP of countries along the“Belt and Road.”The results show that China’s foreign trade technology spillover has a significant institutional quality double threshold effect on the green total factor productivity of the countries along the“Belt and Road.”As the institutional quality of the countries along the“Belt and Road”crosses a specific threshold value,the impact of China’s foreign trade technology spillover on the green total factor productivity of the countries along the“Belt and Road”has a significant positive promoting effect,and corresponding suggestions are put forward. 展开更多
关键词 Technology spillover Green total factor productivity Institutional quality Threshold effect
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Analysis and Strategy Research on Influencing Factors of Classroom Teaching Quality in Higher Vocational Colleges
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作者 Qian Qian Wang Ma.Agatha Anne D.Dizon 《Journal of Contemporary Educational Research》 2024年第4期199-203,共5页
In this study,the questionnaire“Influencing Factors of Classroom Quality in Higher Vocational Education”was self-compiled.By using the questionnaire survey method,the research conclusion was drawn that the main fact... In this study,the questionnaire“Influencing Factors of Classroom Quality in Higher Vocational Education”was self-compiled.By using the questionnaire survey method,the research conclusion was drawn that the main factors affecting the classroom teaching quality in higher vocational education were teaching and student factors,teacher factors,and classroom factors based on 2,683 samples.According to the research results,the measures to improve the quality of classroom teaching are put forward,in order to provide guidance for improving the quality of teaching in higher vocational colleges. 展开更多
关键词 Higher vocational colleges Classroom teaching quality Influencing factor
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Measurement of the cavity-loaded quality factor in superconducting radio-frequency systems with mismatched source impedance
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作者 Jin-Ying Ma Cheng-Ye Xu +12 位作者 An-Dong Wu Guo-Dong Jiang Yue Tao Zong-Heng Xue Long-Bo Shi Tian-Cai Jiang Zheng-Long Zhu Zi-Qin Yang Zheng Gao Lie-Peng Sun Gui-Rong Huang Feng Qiu Yuan He 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第8期12-23,共12页
The accurate measurement of parameters such as the cavity-loaded quality factor(Q_(L))and half bandwidth(f_(0.5))is essential for monitoring the performance of superconducting radio-frequency cavities.However,the conv... The accurate measurement of parameters such as the cavity-loaded quality factor(Q_(L))and half bandwidth(f_(0.5))is essential for monitoring the performance of superconducting radio-frequency cavities.However,the conventional"field decay method"employed to calibrate these values requires the cavity to satisfy a"zero-input"condition.This can be challenging when the source impedance is mismatched and produce nonzero forward signals(V_(f))that significantly affect the measurement accuracy.To address this limitation,we developed a modified version of the"field decay method"based on the cavity differential equation.The proposed approach enables the precise calibration of f_(0.5) even under mismatch conditions.We tested the proposed approach on the SRF cavities of the Chinese Accelerator-Driven System Front-End Demo Superconducting Linac and compared the results with those obtained from a network analyzer.The two sets of results were consistent,indicating the usefulness of the proposed approach. 展开更多
关键词 Loaded quality factor Field decay method Superconducting cavity MISMATCH Calibration Cavity differential equation Measurement Accelerator-driven system
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A WSN Node Fault Diagnosis Model Based on BRB with Self-Adaptive Quality Factor
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作者 Guo-Wen Sun Gang Xiang +3 位作者 Wei He Kai Tang Zi-Yi Wang Hai-Long Zhu 《Computers, Materials & Continua》 SCIE EI 2023年第4期1157-1177,共21页
Wireless sensor networks (WSNs) operate in complex and harshenvironments;thus, node faults are inevitable. Therefore, fault diagnosis ofthe WSNs node is essential. Affected by the harsh working environment ofWSNs and ... Wireless sensor networks (WSNs) operate in complex and harshenvironments;thus, node faults are inevitable. Therefore, fault diagnosis ofthe WSNs node is essential. Affected by the harsh working environment ofWSNs and wireless data transmission, the data collected by WSNs containnoisy data, leading to unreliable data among the data features extracted duringfault diagnosis. To reduce the influence of unreliable data features on faultdiagnosis accuracy, this paper proposes a belief rule base (BRB) with a selfadaptivequality factor (BRB-SAQF) fault diagnosis model. First, the datafeatures required for WSN node fault diagnosis are extracted. Second, thequality factors of input attributes are introduced and calculated. Third, themodel inference process with an attribute quality factor is designed. Fourth,the projection covariance matrix adaptation evolution strategy (P-CMA-ES)algorithm is used to optimize the model’s initial parameters. Finally, the effectivenessof the proposed model is verified by comparing the commonly usedfault diagnosis methods for WSN nodes with the BRB method consideringstatic attribute reliability (BRB-Sr). The experimental results show that BRBSAQFcan reduce the influence of unreliable data features. The self-adaptivequality factor calculation method is more reasonable and accurate than thestatic attribute reliability method. 展开更多
关键词 Self-adaptive quality factor belief rule base wireless sensor networks fault diagnosis
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Factors Associated with Diet Quality in Women of Childbearing Age in Southern Benin in 2022
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作者 Charles Sossa-Jerome Reynald Santos +3 位作者 Lamidhi Salami Clemence Metonnou Colette Azandjeme Moussiliou N Paraiso 《Open Journal of Epidemiology》 2023年第4期421-435,共15页
Background: The nutritional status of women while in pregnancy influences foetus growth, infant development, and the mother’s health. The objective of this study was to assess diet quality and associated factors amon... Background: The nutritional status of women while in pregnancy influences foetus growth, infant development, and the mother’s health. The objective of this study was to assess diet quality and associated factors among women of childbearing age in the Comè community, Benin. Methods: The cross-sectional and analytical study involved 215 participants randomly selected by multi-stage sampling technique. Two non-consecutive dietary recall data were collected as well as sociodemographic information. The International Food Quality Index (IQD-I) was used to assess diet quality. Factors associated with the nutritional quality of the diet were identified by using linear regression. Results: Among 212 women, a diet quality of 175 (82.55%) was fair while 14.62% had good diet quality. Factors associated with the diet quality were the level of household possession, health issues, and nutritional advice at the health care facilities. Conclusion: Nutritional education interventions and income-generating activities may improve the diet quality among women of childbearing age in the Comè in Benin. 展开更多
关键词 Diet quality WOMEN Associated factors BENIN
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Structural characteristics and influencing factors of spatial correlation network for regional high-quality development in China
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作者 LIU Jian-jun LIU He 《Ecological Economy》 2023年第4期329-343,共15页
On the basis of measuring the regional high-quality development in China from 2011 to 2020,this study uses gravity model to build spatial correlation network,and uses social network analysis method to analyze the stru... On the basis of measuring the regional high-quality development in China from 2011 to 2020,this study uses gravity model to build spatial correlation network,and uses social network analysis method to analyze the structural characteristics and influencing factors of correlation network.The results are shown as follows.First,from 2011 to 2020,the level of regional high-quality development in China is rising gradually,and the discrete characteristics between regions are gradually obvious,showing a step-like distribution structure decreasing from east to west.Second,the network density of regional high-quality development is generally low and tends to decline,but it has strong stability and correlation strength.Third,the spatial correlation network has an obvious core-edge structure.Shanghai is always at the center of the network and plays a significant intermediary role,while Qinghai and Xinjiang are always at the edge of the network.Fourth,the regional high-quality development association network can be divided into four major sectors:main benefit,net benefit,net spillover,and broker,showing the spatial correlation characteristics of inter-plate contact and intra-plate agglomeration.Fifth,the level of economic development,the level of urbanization and geographical proximity have a significant impact on the formation of regional high-quality development correlation network. 展开更多
关键词 high quality development spatial association network influencing factors social network analysis
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Study into the Applicability of Laser Beam Quality Factor M^2 被引量:2
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作者 杨静 田小红 辛建国 《Defence Technology(防务技术)》 SCIE EI CAS 2006年第1期33-36,共4页
The applicable condition of single-frequency laser beam quality factor M^2 is studied. Any real single-frequency laser beam can be classified as Gaussian mode and non-Gaussian mode according to the transverse field di... The applicable condition of single-frequency laser beam quality factor M^2 is studied. Any real single-frequency laser beam can be classified as Gaussian mode and non-Gaussian mode according to the transverse field distribution. Non-Gaussian transverse field distribution can be analytically expressed as the sum of Hermite-Gaussian functions. The propagation function and M^2 factor expression for non-Gaussian mode can be obtained by the second moment definition of laser beam spot. The analytical results show, the same as that of Gaussian mode, that the propagation function follows the hyperbolic law and the value of M^2 factor is a constant for non-Gaussian mode. But, different non-Gaussian field distributions may have the same M^2 value. That means M^2 factor cannot reflect the quality of non-Gaussian laser beams correctly. We conclude that the M^2 factor is applicable only to ideal Gaussian laser beam generated by stable resonators. 展开更多
关键词 高斯波束 激光束 适用性 激光武器
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Quality of life of hospitalized patients after lung cancer operation and analysis of influencing factors
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作者 HU Yi‑fan HUANG Xiu‑ming +8 位作者 XIAO Sha ZHOU Jing WANG Shuo‑min WU Qi‑sheng ZHOU Bing‑xian FAN Shi‑heng FAN Ya‑yan CHEN Xian‑shan ZHANG Jing 《Journal of Hainan Medical University》 CAS 2023年第12期41-46,共6页
Objective:To explore the current status and influencing factors of quality of life in patients with lung cancer after surgery in a tertiary hospital in Hainan province.Methods:To investigate the influencing factors of... Objective:To explore the current status and influencing factors of quality of life in patients with lung cancer after surgery in a tertiary hospital in Hainan province.Methods:To investigate the influencing factors of quality of life of lung cancer patients after surgery in a tertiary hospital in Hainan province by cross‑sectional survey method.Results:The scores of insomnia,appetite loss,constipation and pain in 186 lung cancer patients after surgery in a tertiary hospital in Hainan Province were significantly higher than the reference value.Multiple linear regression analysis showed that older patients(>60 years)had lower scores in physical function domain(β=-0.193),and female patients had more appetite loss symptoms(β=0.245).Compared with other minority ethnic groups,Han ethnic group had lower scores in role function domain(β=0.179),more severe fatigue symptoms(β=-0.162),and higher general health level(β=0.166).Patients with employee medical insurance had lower scores of emotional function(β=0.194),cognitive function(β=0.281),the lowest score in social function(β=0.188),and severe pain in other parts(β=-0.227).Smokers had less cough symptoms(β=0.175)and more arm and shoulder pain symptoms(β=-0.21)than non‑smokers.Patients with secondhand smoke exposure had lower cognitive function scores(β=-0.158)and more obvious symptoms of oral ulcer(β=0.185).Patients who drank alcohol frequently(drinking frequency>1 time/day)had more severe cough symptoms(β=0.27).Patients with small number of children(0‑1)had milder cough symptoms(β=0.178).Patients who did not understand the disease had obvious symptoms of arm and shoulder pain(β=0.151).Patients with early pathological stage(stageⅠ‑Ⅱ)had more severe shortness of breath(β=-0.159)and pain(β=-0.181).The symptoms of appetite loss were more obvious in patients living in cities(β=0.192).The symptoms of peripheral neuropathy were more obvious(β=0.174).Patients who often consumed pickulated food had severe pain symptoms(β=-0.219),and pain in other parts was obvious(β=-0.149).Male patients had obvious alopecia symptoms(β=-0.306).Conclusion:Age,ethnicity,residence,type of medical insurance,number of children,pathological stage of lung cancer,smoking,second‑hand smoke exposure,alcohol consumption,and frequent consumption of pickled food were related to the quality of life of lung cancer patients in hospital after surgery.Medical staff and family members should pay attention to the emotional communication of patients during the treatment of lung cancer patients in hospital after surgery.Patients should avoid exposure to smoking,alcohol and second‑hand smoke,and reduce consumption of pickled food. 展开更多
关键词 Lung cancer Patients in hospital after lung cancer SURGERY quality of life The influencing factors Regression analysis
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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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Block Incremental Dense Tucker Decomposition with Application to Spatial and Temporal Analysis of Air Quality Data
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作者 SangSeok Lee HaeWon Moon Lee Sael 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期319-336,共18页
How can we efficiently store and mine dynamically generated dense tensors for modeling the behavior of multidimensional dynamic data?Much of the multidimensional dynamic data in the real world is generated in the form... How can we efficiently store and mine dynamically generated dense tensors for modeling the behavior of multidimensional dynamic data?Much of the multidimensional dynamic data in the real world is generated in the form of time-growing tensors.For example,air quality tensor data consists of multiple sensory values gathered from wide locations for a long time.Such data,accumulated over time,is redundant and consumes a lot ofmemory in its raw form.We need a way to efficiently store dynamically generated tensor data that increase over time and to model their behavior on demand between arbitrary time blocks.To this end,we propose a Block IncrementalDense Tucker Decomposition(BID-Tucker)method for efficient storage and on-demand modeling ofmultidimensional spatiotemporal data.Assuming that tensors come in unit blocks where only the time domain changes,our proposed BID-Tucker first slices the blocks into matrices and decomposes them via singular value decomposition(SVD).The SVDs of the time×space sliced matrices are stored instead of the raw tensor blocks to save space.When modeling from data is required at particular time blocks,the SVDs of corresponding time blocks are retrieved and incremented to be used for Tucker decomposition.The factor matrices and core tensor of the decomposed results can then be used for further data analysis.We compared our proposed BID-Tucker with D-Tucker,which our method extends,and vanilla Tucker decomposition.We show that our BID-Tucker is faster than both D-Tucker and vanilla Tucker decomposition and uses less memory for storage with a comparable reconstruction error.We applied our proposed BID-Tucker to model the spatial and temporal trends of air quality data collected in South Korea from 2018 to 2022.We were able to model the spatial and temporal air quality trends.We were also able to verify unusual events,such as chronic ozone alerts and large fire events. 展开更多
关键词 Dynamic decomposition tucker tensor tensor factorization spatiotemporal data tensor analysis air quality
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Energy beam-based direct and assisted polishing techniques for diamond:A review
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作者 Zhuo Li Feng Jiang +7 位作者 Zhengyi Jiang Zige Tian Tian Qiu Tao Zhang Qiuling Wen Xizhao Lu Jing Lu Hui Huang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期93-124,共32页
Diamond is a highly valuable material with diverse industrial applications,particularly in the fields of semiconductor,optics,and high-power electronics.However,its high hardness and chemical stability make it difficu... Diamond is a highly valuable material with diverse industrial applications,particularly in the fields of semiconductor,optics,and high-power electronics.However,its high hardness and chemical stability make it difficult to realize high-efficiency and ultra-low damage machining of diamond.To address these challenges,several polishing methods have been developed for both single crystal diamond(SCD)and polycrystalline diamond(PCD),including mechanical,chemical,laser,and ion beam processing methods.In this review,the characteristics and application scope of various polishing technologies for SCD and PCD are highlighted.Specifically,various energy beam-based direct and assisted polishing technologies,such as laser polishing,ion beam polishing,plasma-assisted polishing,and laser-assisted polishing,are summarized.The current research progress,material removal mechanism,and infuencing factors of each polishing technology are analyzed.Although some of these methods can achieve high material removal rates or reduce surface roughness,no single method can meet all the requirements.Finally,the future development prospects and application directions of different polishing technologies are presented. 展开更多
关键词 single crystal diamond polycrystalline diamond energy beam polishing technology material removal mechanism influencing factors
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Investigation and Analysis of Factors Influencing the Quality of Community Nursing Services in Laishan District,Yantai City
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作者 Jianjun Sun Qing Ji +1 位作者 Arby James Abonalla Minerva B.De Ala 《Journal of Clinical and Nursing Research》 2023年第6期230-234,共5页
Objective:The purpose of this study is to conduct an in-depth investigation and analysis of the factors affecting the quality of community nursing services in Laishan District,Yantai City,and provide suggestions for i... Objective:The purpose of this study is to conduct an in-depth investigation and analysis of the factors affecting the quality of community nursing services in Laishan District,Yantai City,and provide suggestions for improving the quality of the services.Method:The community nursing services in Laishan District,Yantai City were investigated through questionnaires and on-site observations.Result:The content of nursing services was correlated with the professional titles of the staff.The guidance given to patients and caregivers was significantly correlated with the educational level of community nursing personnel.Therefore,this indicates that the professional titles and educational backgrounds of the community nursing personnel have a significant impact on the quality of service provided.Conclusion:The role of professional title evaluation can be optimized,further enhancing the educational level of nurses in surrounding communities,optimizing service content and methods,etc.,in order to improve the quality of community nursing services in the region. 展开更多
关键词 Laishan District Community nursing Service quality Influencing factors
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Dynamic Response Impact of Vehicle Braking on Simply Supported Beam Bridges with Corrugated Steel Webs Based on Vehicle-Bridge Coupled Vibration Analysis
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作者 Yan Wang Siwen Li Na Wei 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期3467-3493,共27页
A novel approach for analyzing coupled vibrations between vehicles and bridges is presented,taking into account spatiotemporal effects and mechanical phenomena resulting fromvehicle braking.Efficient modeling and solu... A novel approach for analyzing coupled vibrations between vehicles and bridges is presented,taking into account spatiotemporal effects and mechanical phenomena resulting fromvehicle braking.Efficient modeling and solution of bridge vibrations induced by vehicle deceleration are realized using this method.The method’s validity and reliability are substantiated through numerical examples.A simply supported beam bridge with a corrugated steel web is taken as an example and the effects of parameters such as the initial vehicle speed,braking acceleration,braking location,and road surface roughness on the mid-span displacement and impact factor of the bridge are analyzed.The results show that vehicle braking significantly amplifies mid-span displacement and impact factor responses in comparison to uniform vehicular motion across the bridge.Notably,the influence of wheelto-bridge friction forces is of particular significance and cannot be overlooked.When the vehicle initiates braking near the middle of the span,both the mid-span displacement and impact factor of the bridge exhibit substantial increases,further escalating with higher braking acceleration.Under favorable road surface conditions,the midspan displacement and the impact factor during vehicle braking may exceed the design values stipulated by codes.It is important to note that road surface roughness exerts a more pronounced effect on the impact factor of the bridge in comparison to the effects of vehicle braking. 展开更多
关键词 Corrugated steel web girder bridges simply supported beam bridges vehicle-bridge coupled vibration BRAKING impact factor
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Epidemiological, Clinical Aspects and Factors Associated with Typical Gastroesophageal Reflux Disease in the General Population of Parakou, Republic of Benin
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作者 Saké Khadidjatou Tamou Sambo Bio Elie +3 位作者 Zinsou Jocelyne Abla Dovonou Comlan Albert Sehonou Jean Kodjoh Nicolas 《Open Journal of Gastroenterology》 CAS 2024年第2期41-58,共18页
Introduction: Gastroesophageal reflux disease (GERD) is a benign and chronic disease that can impair the quality of life. Objective: To study the epidemiological, clinical aspects and factors associated with typical G... Introduction: Gastroesophageal reflux disease (GERD) is a benign and chronic disease that can impair the quality of life. Objective: To study the epidemiological, clinical aspects and factors associated with typical GERD in the general population of Parakou in the Republic of Benin. Methods: This was a descriptive and analytical cross-sectional study with prospective data collection which took place from May 1, 2019 to June 30, 2019. The study population consisted of any subject aged at least 15 years and living in Parakou. Subjects aged at least 15 years, present on the day of the survey and having given their free and informed verbal consent were included. The Short form of QRS®(Reflux-Qual Short form) questionnaire and the “Hospital Anxiety and Depression” score were used to assess the quality of life and anxiety/depression, respectively. The sampling was probabilistic through a 2-stage cluster sampling. The variable of interest was the presence of GERD. Results: Out of 390 subjects surveyed, 28 had symptoms of typical GERD, representing a prevalence of 7.18%. The average age of these subjects was 27.11 ± 7.88 years. Fifteen subjects (53.57%) were male, giving a sex ratio of 1.15. Fourteen (50%) had a secondary level of education, 12 (42.86%) were pupils/students, 18 (64.29%) were single. The monthly income of 22 subjects (78.57%) was lower than the guaranteed interprofessional minimum wage (40,000 FCFA). The average duration of progression of symptoms was 15.89 ± 4.97 months. Symptoms occurred less than twice a week in 22 subjects (78.57%). The clinical manifestations were both diurnal and nocturnal in 12 subjects (42.86%). None of the 28 subjects with GERD had clinical warning signs. Asthma, diabetes, consumption of high fat or spice foods, carbonated drinks, non-steroidal anti-inflammatory drugs, alcoholic beverages and tobacco were statistically associated with the occurrence of GERD. Each of the 28 subjects had at least one associated factor. A significant impair in quality of life was observed in 27 patients (96.43%). Conclusion: Typical GERD is relatively common in the general population of Parakou in the Republic of Benin. It often affects young males. Among the risk factors identified, the most common are carbonated drinks, spicy meals and diabetes. GERD significantly impairs quality of life. Raising awareness about the disease and its associated factors is necessary among the general population. 展开更多
关键词 Gastroesophageal Reflux Disease EPIDEMIOLOGY General Population Associated factors quality of Life Parakou
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Lifestyle: an underrated but potentially important influencing factor on semen quality
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作者 Wen-Kang Chen He-De Zou +2 位作者 Han-Fei Liu Bo-Lin Li Jia-You Zhao 《Clinical Research Communications》 2023年第3期16-21,共6页
Lifestyle factors play a crucial role in the influence of semen quality,and they are especially significant in the context of traditional Chinese medicine(TCM)clinical treatment for poor semen quality.TCM theory empha... Lifestyle factors play a crucial role in the influence of semen quality,and they are especially significant in the context of traditional Chinese medicine(TCM)clinical treatment for poor semen quality.TCM theory emphasizes the importance of healthy lifestyle habits for overall well-being.Therefore,it is essential to consider lifestyle factors in the clinical management of TCM and semen quality.Lifestyle can act as a bias factor that affects research quality,making it vital to pay special attention to its impact in clinical trial research on male semen quality.This article aims to improve the quality and design of clinical research on male sperm quality by examining the effects of various lifestyle factors on semen quality,including physical activities,dietary patterns,smoking,alcohol consumption,coffee intake,sleep,and psychological stress.Each lifestyle factor has its own distinct influence on semen quality,and there is a synergistic effect when multiple lifestyle factors are combined.These findings emphasize the need for careful consideration of lifestyle factors and their interactions in the design and implementation of TCM clinical trial research. 展开更多
关键词 lifestyle factors semen quality traditional Chinese medicine clinical trial research synergistic effect
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Assessment on eco-environmental quality of the Yellow River Basin by considering desertification index
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作者 AN Min MENG Fan +4 位作者 HE Weijun XUE Fang SONG Mengfei XIE Ping WANG Bei 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3275-3292,共18页
Desertification has had a significant impact on the ecological environment of the Yellow River Basin(YRB)in China.However,previous studies on the evaluation of the ecological environment quality(EEQ)in the YRB have pa... Desertification has had a significant impact on the ecological environment of the Yellow River Basin(YRB)in China.However,previous studies on the evaluation of the ecological environment quality(EEQ)in the YRB have paid limited attention to the indicator of desertification.It is of great significance to incorporate the desertification index into the spatiotemporal assessment of the EEQ in the YRB in order to protect the ecological environment in the region.In this study,based on multi-source remote sensing data from 91 cities in the YRB,this article proposes a desertification remote sensing ecological index(DRSEI)model,which builds upon the traditional Remote Sensing Ecological Index(RSEI)model,to analyze the spatiotemporal changes in the EEQ in the YRB from 2001 to 2021.Furthermore,using the geographic detector(GD),and geographically and temporally weighted regression(GTWR)model,the study assesses the impact of human and natural factors on the EEQ in the YRB.The research findings indicate that:(1)Compared to the traditional RSEI,the improved DRSEI shows a decreasing trend in the evaluation results of the EEQ.Among the 24 cities,the change in DRSEI exceeds 0.05 compared to RSEI,accounting for 26.37%of the YRB.The remaining 67 cities have changes within a range of less than 0.05,accounting for 73.63%of the YRB.(2)The results of the GD for individual and interactive effects reveal that rainfall and elevation have significant individual and interactive effects on the EEQ.Furthermore,after the interaction with natural factors,the explanatory power of human factors gradually increases over time.The spatial heterogeneity results of GTWR demonstrate that rainfall has a strong direct positive impact on the EEQ,accounting for 98.90%of the influence,while temperature exhibits a more pronounced direct inhibitory effect,accounting for 76.92%of the influence.Human activities have a strong negative impact on the EEQ and a weak positive impact. 展开更多
关键词 Ecological environment quality Desertification index Desertification remote sensing ecological index Driving factors Yellow River Basin
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