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Research on Multi-Level Automatic Filling Optimization Design Method for Layered Cross-Sectional Layout of Umbilical 被引量:1
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作者 YIN Xu FAN Zhi-rui +4 位作者 CAO Dong-hui LIU Yu-jie LI Meng-shu YAN Jun YANG Zhi-xun 《China Ocean Engineering》 2025年第5期891-903,共13页
The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly comple... The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly complex layout combinations.Furthermore,due to constraints in component quantity and geometry within the cross-sectional layout,filler bodies must be incorporated to maintain cross-section performance.Conventional design approaches based on manual experience suffer from inefficiency,high variability,and difficulties in quantification.This paper presents a multi-level automatic filling optimization design method for umbilical cross-sectional layouts to address these limitations.Initially,the research establishes a multi-objective optimization model that considers compactness,balance,and wear resistance of the cross-section,employing an enhanced genetic algorithm to achieve a near-optimal layout.Subsequently,the study implements an image processing-based vacancy detection technique to accurately identify cross-sectional gaps.To manage the variability and diversity of these vacant regions,the research introduces a multi-level filling method that strategically selects and places filler bodies of varying dimensions,overcoming the constraints of uniform-size fillers.Additionally,the method incorporates a hierarchical strategy that subdivides the complex cross-section into multiple layers,enabling layer-by-layer optimization and filling.This approach reduces manufac-turing equipment requirements while ensuring practical production process feasibility.The methodology is validated through a specific umbilical case study.The results demonstrate improvements in compactness,balance,and wear resistance compared with the initial cross-section,offering novel insights and valuable references for filler design in umbilical cross-sections. 展开更多
关键词 UMBILICAL cross-sectional layout multi-level filling layered layout optimization design
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The Increasing Trends of Short and Long Sleep Duration among Chinese Adults from 2010 to 2018:A Repeated Nationally Representative Cross-sectional Survey
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作者 Yun Chen Lan Wang +12 位作者 Mei Zhang Sifan Hu Yan Shao Xiao Zhang Chun Li Jie Chen Zhenping Zhao Yanhong Dong Lin Lu Maigeng Zhou Limin Wang Junliang Yuan Hongqiang Sun 《Biomedical and Environmental Sciences》 2026年第1期46-59,共14页
Objective This study aimed to determine the temporal trends in sleep duration among Chinese adults.Methods In this series of repeated nationally representative cross-sectional surveys(China Chronic Disease and Risk Fa... Objective This study aimed to determine the temporal trends in sleep duration among Chinese adults.Methods In this series of repeated nationally representative cross-sectional surveys(China Chronic Disease and Risk Factors Surveillance)conducted between 2010 and 2018,a total of 645,420 adult participants(97,741 in 2010;175,749 in 2013;187,777 in 2015;and 184,153 in 2018)were included in the trend analysis.Linear and logistic regression models were utilized to assess trends in sleep duration.Results In 2018,the estimated overall mean sleep duration among the Chinese adult population was7.58(SD,1.45)hours per day,with no significant trend from 2010.A significant increase in short sleep duration(≤6 hours)was observed in the total population,from 15.3%(95%CI:14.1%–16.5%)in 2010 to18.5%(95%CI:17.7%–19.3%)in 2018(P<0.001).Similarly,the trend in long sleep duration(>9 hours)was also significant,increasing in weighted prevalence from 7.2%(95%CI:6.3%–8.1%)in 2010 to 9.0%(95%CI:8.2%–9.9%)in 2018(P<0.001).Conclusion The prevalence of both short and long sleep durations significantly increased among Chinese adults from 2010 to 2018,highlighting the urgency of health initiatives to promote optimal sleep duration in China. 展开更多
关键词 Sleep duration Trend analysis Repeated cross-sectional study Nationally representative survey CCDRFS
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Association between Non-high-density Lipoprotein Cholesterol to High-density Lipoprotein Cholesterol Ratio(NHHR)and Stroke among Adults in the USA:A Cross-Sectional NHANES Study 被引量:2
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作者 Haixia Ma Huaqiu Chen Peichang Wang 《Biomedical and Environmental Sciences》 2025年第1期37-46,共10页
Objective The relationship between non-high-density lipoprotein(NHDL)cholesterol to high-density lipoprotein cholesterol(HDL-C)ratio(NHHR)and stoke remains unknown.This study aimed to evaluate the association between ... Objective The relationship between non-high-density lipoprotein(NHDL)cholesterol to high-density lipoprotein cholesterol(HDL-C)ratio(NHHR)and stoke remains unknown.This study aimed to evaluate the association between the adult NHHR and stroke occurrence in the United States of America(USA).Methods To clarify the relationship between the NHHR and stroke risk,this study used a multivariable logistic regression model and a restricted cubic spline(RCS)model to investigate the association between the NHHR and stroke,and data from the National Health and Nutrition Examination Survey(NHANES)from 2005 to 2018.Subgroup and sensitivity analyses were conducted to test the robustness of the results.Results This study included 29,928 adult participants,of which 1,165 participants had a history of stroke.Logistic regression analysis of variables demonstrated a positive association between NHHR and stroke(OR 1.24,95%CI:1.03-1.50,P=0.026).Compared with the lowest reference group of NHHR,participants in the second,third,and fourth quartile had a significantly increased risk of stroke after full adjustments(OR:1.35,95%CI:1.08-1.69)(OR:1.83,95%CI:1.42-2.36)(OR:2.04,95%CI:1.50-2.79).In the total population,a nonlinear dose-response relationship was observed between the NHHR and stroke risk(P non-linearity=0.002).This association remained significant in several subgroup analyses.Further investigation of the NHHR may enhance our understanding of stroke prevention and treatment.Conclusion Our findings suggest a positive correlation between the NHHR and an increased prevalence of stroke,potentially serving as a novel predictive factor for stroke.Timely intervention and management of the NHHR may effectively mitigate stroke occurrence.Prospective studies are required to validate this association and further explore the underlying biological mechanisms. 展开更多
关键词 NHHR STROKE NHANES cross-sectional study
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Occupational influences on dietary quality among postpartum women:a cross-sectional study in Beijing,China 被引量:1
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作者 Jian Zhao Min Zhang 《Global Health Journal》 2025年第2期94-103,共10页
Objective:Postpartum nutrition plays a critical role in maternal recovery and long-term health.However,the nutritional status of working mothers in the postpartum period remains understudied.This study aimed to assess... Objective:Postpartum nutrition plays a critical role in maternal recovery and long-term health.However,the nutritional status of working mothers in the postpartum period remains understudied.This study aimed to assess the dietary quality of postpartum women in urban Beijing,identify occupational-related factors influencing their diet,and explore potential interventions to improve maternal nutrition during the postpartum period.Methods:In this cross-sectional analysis,554 women one year after delivery were recruited from ten community health centers.Sociodemographic,occupational and postpartum care variables were collected via questionnaire.Dietary intake over the preceding year was assessed using a food frequency questionnaire.The modified dietary balance index for postpartum women were used for dietary quality assessment.Results:The study revealed severe dietary imbalances among postpartum women,characterized by excessive consumption of cereals,eggs,and meats,while their intake of vegetables,fruits,and dairy products was inadequate.According to dietary balance index for postpartum women,66.25%of mothers showed varying degrees of excessive intake.45.31%of mothers experienced varying levels of insufficient intake,with only 19.86%of participants having a relatively balanced diet.Occupational differences were observed,with women in the commercial employment group showing higher levels of excessive food intake.The analysis of influencing factors showed that family monthly income,maternity leave,and postpartum care significantly affected the dietary quality.Conclusions:Postpartum women in Beijing experience widespread dietary imbalances,with both excesses and deficiencies.Occupational context and related factors significantly shape diet quality.These findings highlight the need for targeted nutritional interventions tailored to the specific challenges of different occupational groups. 展开更多
关键词 Postpartum dietary quality Dietarybalance index Occupational factors Maternal health cross-sectional study
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Gut microbial characteristics of the damp-heat constitution:a population-based multicenter cross-sectional study 被引量:1
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作者 LI Tianxing ZHU Linghui +9 位作者 WANG Xueke TANG Jun YANG Lingling PANG Guoming LI Huang WANG Liying DONG Yang ZHAO Shipeng LI Yingshuai LI Lingru 《Journal of Traditional Chinese Medicine》 2025年第1期140-151,共12页
OBJECTIVE:To investigate the difference in gut microbiota between population with damp-heat constitution(DHC)and balanced constitution(BC).METHODS:A multi-centered cross-sectional casecontrol study was conducted,which... OBJECTIVE:To investigate the difference in gut microbiota between population with damp-heat constitution(DHC)and balanced constitution(BC).METHODS:A multi-centered cross-sectional casecontrol study was conducted,which included 249 participants with damp-heat constitution or balanced constitution.Baseline information of participants was collected,and stool samples were collected for gut microbiota analysis.Principal coordinate analysis,linear discriminant analysis effect size analysis,receiver operating characteristic,random forest model,and phylogenetic investigation of communities by reconstruction of unobserved states methods were used to reveal the relationship between gut microbiota and the damp-heat constitution.RESULTS:Compared to those in the BC group,the richness and diversity of the microbiota,specifically those of several short-chain fatty acid producing genera such as Barnesiella,Coprobacter,and Butyricimonas,were significantly decreased in the DHC group.Regarding biological functions,flavonoid biosynthesis,propanoate metabolism,and nucleotide sugar metabolism were suppressed,while arachidonic acid metabolism and glutathione metabolism were enriched in the DHC group.Finally,a classifier based on the microbiota was constructed to discriminate between the DHC and BC populations.CONCLUSION:The gut microbiota of the DHC population exhibits significantly reduced diversity and is closely related to inflammation,metabolic disorders,and liver steatosis,which is consistent with clinical observations,thus serving as a potential diagnostic tool for traditional Chinese medicine constitution discrimination. 展开更多
关键词 damp-heat constitution balanced constitution Traditional Chinese medicine constitution MICROBIOTA inflammatory PICRUSt multicenter study cross-sectional studies
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Optimization Design of the Multi-Layer Cross-Sectional Layout of An Umbilical Based on the GA-GLM 被引量:1
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作者 YANG Zhi-xun YIN Xu +5 位作者 FAN Zhi-rui YAN Jun LU Yu-cheng SU Qi MAO Yandong WANG Hua-lin 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期247-254,共8页
Marine umbilical is one of the key equipment for subsea oil and gas exploitation,which is usually integrated by a great number of different functional components with multi-layers.The layout of these components direct... Marine umbilical is one of the key equipment for subsea oil and gas exploitation,which is usually integrated by a great number of different functional components with multi-layers.The layout of these components directly affects manufacturing,operation and storage performances of the umbilical.For the multi-layer cross-sectional layout design of the umbilical,a quantifiable multi-objective optimization model is established according to the operation and storage requirements.Considering the manufacturing factors,the multi-layering strategy based on contact point identification is introduced for a great number of functional components.Then,the GA-GLM global optimization algorithm is proposed combining the genetic algorithm and the generalized multiplier method,and the selection operator of the genetic algorithm is improved based on the steepest descent method.Genetic algorithm is used to find the optimal solution in the global space,which can converge from any initial layout to the feasible layout solution.The feasible layout solution is taken as the initial value of the generalized multiplier method for fast and accurate solution.Finally,taking umbilicals with a great number of components as examples,the results show that the cross-sectional performance of the umbilical obtained by optimization algorithm is better and the solution efficiency is higher.Meanwhile,the multi-layering strategy is effective and feasible.The design method proposed in this paper can quickly obtain the optimal multi-layer cross-sectional layout,which replaces the manual design,and provides useful reference and guidance for the umbilical industry. 展开更多
关键词 UMBILICAL cross-sectional layout MULTI-LAYERS GA-GLM optimization
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基于MATLAB App Designer的数字岩心建模软件设计与开发
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作者 左艳彤 邢兰昌 +1 位作者 贾宁洪 刘宝 《计算机测量与控制》 2026年第1期235-243,共9页
为解决现有商用数字岩心建模软件功能可扩展性弱、成本高等问题,文章基于MATLAB App Designer工具开发了一款集成化的数字岩心建模软件,该软件包括图像处理、图像分析和孔隙网络提取等三大功能模块;图像处理模块集成了中值滤波、高斯滤... 为解决现有商用数字岩心建模软件功能可扩展性弱、成本高等问题,文章基于MATLAB App Designer工具开发了一款集成化的数字岩心建模软件,该软件包括图像处理、图像分析和孔隙网络提取等三大功能模块;图像处理模块集成了中值滤波、高斯滤波、SUSAN平滑、图像锐化及阈值分割等多种图像处理算法;图像分析模块采用多平面切片与序列叠加方法、借助三维交互技术实现了岩心结构的三维可视化、切面展示与旋转浏览;孔隙网络提取模块采用最大球法提取孔隙网络,从而获取配位数、孔隙半径、孔隙体积等关键结构参数,利用直方图对结构参数分布进行统计分析;利用典型岩心样本对所开发的软件进行功能测试,结果表明:该软件功能集成度高、界面友好、操作简便,能够有效提升图像质量、对岩心图像进行三维可视化展示以及准确提取三维岩心的孔隙网络结构特征;软件具备良好的可扩展性和二次开发潜力,为后续开发数字岩心电学、声学、核磁共振等响应的数值仿真模块提供了前提。 展开更多
关键词 数字岩心 MATLAB App designer 图像处理 图像分析 孔隙网络提取
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Characteristics and trends of bibliometric analysis on acupuncture:A cross-sectional study
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作者 Zhi-Qiang Li Hui-Juan Cao +9 位作者 Heng Yin Yue Jiang Xue-Feng Wang Chen Shen Kun Wu Zi-Yi Qi Mei-Ling Wang You-Zhu Su Ling-Yao Kong Jian-Ping Liu 《Integrative Medicine Discovery》 2025年第3期1-11,共11页
Background:The bibliometrics of acupuncture are growing rapidly.However,the absence of reporting guidelines may lead to significant duplication and waste,thereby undermining the research’s value.To address this,a kno... Background:The bibliometrics of acupuncture are growing rapidly.However,the absence of reporting guidelines may lead to significant duplication and waste,thereby undermining the research’s value.To address this,a knowledge mapping was generated based on published studies to investigate the characteristics of bibliometric studies on acupuncture and the extent of duplicate publications,with the overarching goal of providing a comprehensive overview of the knowledge structure in this field.Methods:This cross-sectional study used three databases(PubMed,Web of Science,and Scopus)to identify relevant studies up to May 1,2024.In addition,the reference lists were retrieved as a supplement.To track research trends,we employed Microsoft Excel and R software to extract,code,and analyze information.Study selection,data extraction,and validation were performed independently by at least two reviewers.The reporting quality of included studies was assessed using the Preliminary guideline for reporting bibliometric reviews of the biomedical literature(BIBLIO).Results:Among the 6,221 bibliometric reviews examined,113 relevant publications were identified,80 focusing on various diseases/conditions.The annual number of publications has gradually increased,with the output in the past four years being 3.52 times higher than that before 2020.China(106)and Chengdu University of Traditional Chinese Medicine(16)have the highest number of publications.The most prolific author is Fan-Rong Liang,with six articles.The first bibliometric study,by Hai-Yan Li,was published in 2010.Journal of Pain Research,with 36 articles,holds the most publications.The top three diseases:diseases of the nervous system;symptoms,signs,or clinical findings not elsewhere classified;and mental,behavioral,or neurodevelopmental disorders.There may be potential duplication in research on 13 diseases/conditions,notably stroke,migraine,pain/analgesia,cancer pain,shoulder pain,facial paralysis/bell’s palsy,chronic pain,and cognitive impairment.In BIBLIO,the most frequently missing items are issues/topics(item 2),quality assessment(item 11),and descriptive findings(item 13).Conclusion:This study demonstrates that acupuncture bibliometrics is actively utilized to identify dominant diseases/conditions,aiding scholars in understand the knowledge structure and main topics.Although the number of related studies is increasing,with an average of 25 studies annually,overlap in some areas highlights the need for adherence to reporting guidelines and careful topic selection to ensure truly valuable insights and knowledge contributions.The adherence to BIBLIO’s 20 proposed items across analyzed articles,highlighting important in reporting practices. 展开更多
关键词 cross-sectional study ACUPUNCTURE BIBLIOMETRICS evidence mapping
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Latent profilesof ambivalence over emotional expression in young breast cancer patients:A cross-sectional study
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作者 Xiaocen Chen Zhao Wang +3 位作者 Sibo Wang Fang Zhang Xueyu Li Jing Zhao 《International Journal of Nursing Sciences》 2025年第4期379-385,I0004,I0005,共9页
Objectives:This study aimed to classify young breast cancer patients into distinct ambivalence over emotional expression and to explore the factors influencingthe level of ambivalence over emotional expression.Methods... Objectives:This study aimed to classify young breast cancer patients into distinct ambivalence over emotional expression and to explore the factors influencingthe level of ambivalence over emotional expression.Methods:A total of 217 young breast cancer patients were enrolled from a tertiary Grade A oncology hospital in Tianjin,China,using the convenience sampling method.All participants completed the general questionnaire,Ambivalence over Emotion Expression Questionnaire(AEQ),and Family Adapt-Ability and Cohesion Evaluation Scales-Chinese Version(FACES-CV).We employed exploratory latent profileanalysis for ambivalence over emotional expression profilingand logistic regression analysis to identify the influentialfactors Results:The results of the latent profileanalysis supported the models of four latent profiles,which were definedas“low conflict-lowexpression reflection”(19.2%),“high conflict-high inhibition expression”(43.9%),“moderate conflict-highregret expression”(18.1%),and“moderate conflict-desire understand”(18.8%).Logistic regression revealed that family cohesion,marital status,residence,per capita monthly income,and cancer stage were the influencingfactors of ambivalence over emotional expression in young breast cancer patients(P<0.05)Conclusions:Levels of ambivalence over emotional expression ameast cancer patients with breast cancer were highly heterogeneous.Medical staff should provide psychological counseling and health education tailored to the unique characteristics of emotional expression ambivalence in different patient groups to promote healthy emotional expression among patients. 展开更多
关键词 AMBIVALENCE Breast neoplasms cross-sectional studies Emotions NURSING Young adult
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Examining emotional intelligence of hospital-based nursing students with comparison between full-time and part-time study modes:A cross-sectional study
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作者 Joanna Hiu Ki Ko Daniel Yee Tak Fong 《Nursing Communications》 2025年第17期1-6,共6页
association with academic and clinical performance.This study aimed to determine the EI level of hospital-based nursing students and examine differences between full-time and part-time students.Methods:We conducted a ... association with academic and clinical performance.This study aimed to determine the EI level of hospital-based nursing students and examine differences between full-time and part-time students.Methods:We conducted a cross-sectional study in a hospital-based nursing school.EI level was measured using the Schutte Self-report Emotional Intelligence Scale(SSEIS).Results:We recruited 287 participants(mean age:21.9 years).Their mean SSEIS score was 119.6(95%CI=118.57-120.65).The mean SSEIS scores of 172 full-time and 115 part-time nurses were 120.7(95%CI=119.3-122.0)and 118.1(95%CI=116.5-119.6),respectively.There was no significant difference between the groups.Conclusion:The EI difference between full-time and part-time nursing students was statistically insignificant.The need for further EI development among both full-time and part-time students must be addressed. 展开更多
关键词 emotional intelligence nursing education nursing students HOSPITAL-BASED FULL-TIME PART-TIME cross-sectional study
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Parent interactions and physical aggression among Indonesian adolescents:a cross-sectional study
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作者 Yoyok Bekti Pasetyo Alifya Az Zahra +5 位作者 Sri Sunaringsih Ika Wardojo Nur Melizza Anggraini Dwi Kurnia Nur Lailatul Masruroh Titih Huriah Rusnani Ab Latif 《Frontiers of Nursing》 2025年第3期345-354,共10页
Objective:This study aimed to examine the association between parent-child relationships and physically aggressive behavior among adolescents.Methods:This is a cross-sectional study that uses secondary data from the 2... Objective:This study aimed to examine the association between parent-child relationships and physically aggressive behavior among adolescents.Methods:This is a cross-sectional study that uses secondary data from the 2015 Indonesia Global School-Based Health Survey(IGSHS).Health surveys were conducted in 75 schools representing three regions(Sumatra,Java-Bali;Outer Sumatra;and Java-Bali)in 26 provinces and 68 districts/cities in Indonesia(N=10,139 students).Students who participated were aged 12-19 years,were enrolled in public schools in the junior and high school levels.Results:It has been seen that for most middle-aged adolescents(58.7%),their parents(25%-29%)pay less attention to academic assignments(homework),problems,and use of free time.The most significant factors that influence adolescents to commit violence are smoking and consuming alcohol.Adolescents who smoke are twice as likely to commit physical violence compared with adolescents who do not smoke(OR=2.005;95%CI=1.7062-2.396).Meanwhile,adolescents who consume alcohol are 1.8 times more likely to commit physical violence compared with adolescents who do not consume alcohol(OR=1.807;95%CI=1.421-2.298).Conclusions:Through educational activities and consultations,this study’s findings are valuable for establishing parenting programs among those concerned about their children’s aggressive behavior.Meanwhile,counseling programs can be started in schools by conducting self-detection of negative adolescent behavior,such as screening for smoking,alcohol consumption,sleep issues,and attempted suicide. 展开更多
关键词 parent-child relations adolescent behavior SMOKING alcohol drinking VIOLENCE cross-sectional studies Indonesia
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Associations between qi stagnation constitution,suboptimal health status,and lifestyle factors in southern China:A population-based cross-sectional study
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作者 Haiyun Zhang Jieyu Chen +7 位作者 Jieling Chen Yangzhi Liu Jiahui Yu Ji Wang Yumei Zhou Longmei Yu Hiu Yee Kwan Xiaoshan Zhao 《Journal of Traditional Chinese Medical Sciences》 2025年第4期521-530,共10页
Objective:To study the relationship between qi stagnation constitution and suboptimal health status(SHS)or lifestyle.Methods:From 2012 to 2013,we conducted a cross-sectional survey of 24159 Chinese individuals aged 12... Objective:To study the relationship between qi stagnation constitution and suboptimal health status(SHS)or lifestyle.Methods:From 2012 to 2013,we conducted a cross-sectional survey of 24159 Chinese individuals aged 12-80 years.The qi stagnation constitution was assessed using the Constitution in Chinese Medicine Questionnaire.Health status was evaluated through medical records and the Subhealth Measurement Scale V1.0(SHMS V1.0).Health-promoting lifestyles were measured using the Health-Promoting Lifestyle Profile Ⅱ(HPLP-Ⅱ).Results:Of the 24159 participants,16.1%and 15.2%were classified as“always”and“sometimes”having the qi stagnation constitution,respectively.Those classified as“rarely”having the qi stagnation constitution scored higher on both the HPLP-Ⅱ and SHMS V1.0.The participants classified as“always”having the qi stagnation constitution showed a significant association with SHS or disease compared to other imbalanced constitutions.Those in the“always”category were approximately 21 times more likely to be classified as having SHS(odds ratio[OR]:21.17,95%confidence interval[CI]:15.74-28.45),whereas those in the“sometimes”category were approximately six times more likely(OR:5.89,95%CI:5.04-6.90).Accordingly,the qi stagnation constitution score was significantly associated with the diagnosis of SHS,with an area under the curve of 0.77(P<.001).A score of 18.75 yielded the highest Youden Index(0.407),with a sensitivity of 60.5%and a specificity of 80.3%.Significant associations were observed between health-promoting lifestyles and qi stagnation constitution severity in an ordinal regression analysis(P<.001).Protective factors included stress management(OR:1.59),self-actualization(OR:1.57),and exercise(OR:1.36).In contrast,poorer interpersonal relationships(OR:0.79),greater health responsibilities(OR:0.86),and poorer nutrition(OR:0.91)were associated with increased severity.Conclusion:Modulating the qi stagnation constitution through lifestyle interventions may help prevent the progression of SHS to disease,which aligns with core preventive principles in traditional Chinese medicine. 展开更多
关键词 Qi stagnation constitution Suboptimal health status Health-promoting lifestyle Traditional Chinese medicine constitution cross-sectional study
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Response of River Cross-Sectional Characteristics to Tidally Driven Diversion-Drainage Regulation
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作者 LI Shou-qian HU Rui +4 位作者 ZHANG Rui WANG Zhi-li LIU Huai-xiang ZHOU Shi-huan XU Xian-zi 《China Ocean Engineering》 2025年第6期1083-1096,共14页
The downstream region of the Yangtze River in China experiences tidal influences, with most tributary inlets regulated by hydraulic hubs that control water diversion and drainage. The cross-sectional characteristics o... The downstream region of the Yangtze River in China experiences tidal influences, with most tributary inlets regulated by hydraulic hubs that control water diversion and drainage. The cross-sectional characteristics of these rivers under intermittent diversion and drainage remain uncertain due to various boundary conditions, including tidal fluctuations from the Yangtze River, hydraulic hub operations, and tributary water levels. This study examines the Yanglintang River as a case study, utilizing a two-dimensional water-sediment numerical model to analyze the response of river cross-sections under varying diversion-to-drainage ratios. The findings demonstrate that river cross-sections transform from a regular trapezoidal shape to a pot-bottom configuration, achieving equilibrium within 2 to 3 years under the influence of water diversion and drainage. The operational duration of water diversion and drainage shows minimal impact on river cross-sectional morphology, with bed scouring reaching approximately 10 cm when the operational duration doubles. However, the flow rate of water diversion-drainage operations emerges as the primary factor controlling river cross-sectional morphology, resulting in bed scouring magnitude of approximately 1 m under doubled flow rate conditions. 展开更多
关键词 tide-influenced river diversion-drainage duration diversion-drainage flow rate cross-sectional morphology erosion and deposition trends
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3D Model Reconstruction of Aluminum Foam Cross-Sectional Sequence Images Based on Milling
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作者 Xu Feng Zhiguo Dong +1 位作者 Bo Li Hui Peng 《Journal of Beijing Institute of Technology》 2025年第5期458-481,共24页
This study introduces a novel method for reconstructing the 3D model of aluminum foam using cross-sectional sequence images.Combining precision milling and image acquisition,high-qual-ity cross-sectional images are ob... This study introduces a novel method for reconstructing the 3D model of aluminum foam using cross-sectional sequence images.Combining precision milling and image acquisition,high-qual-ity cross-sectional images are obtained.Pore structures are segmented by the U-shaped network(U-Net)neural network integrated with the Canny edge detection operator,ensuring accurate pore delineation and edge extraction.The trained U-Net achieves 98.55%accuracy.The 2D data are superimposed and processed into 3D point clouds,enabling reconstruction of the pore structure and aluminum skeleton.Analysis of pore 01 shows the cross-sectional area initially increases,and then decreases with milling depth,with a uniform point distribution of 40 per layer.The reconstructed model exhibits a porosity of 77.5%,with section overlap rates between the 2D pore segmentation and the reconstructed model exceeding 96%,confirming high fidelity.Equivalent sphere diameters decrease with size,averaging 1.95 mm.Compression simulations reveal that the stress-strain curve of the 3D reconstruction model of aluminum foam exhibits fluctuations,and the stresses in the reconstruction model concentrate on thin cell walls,leading to localized deformations.This method accurately restores the aluminum foam’s complex internal structure,improving reconstruction preci-sion and simulation reliability.The approach offers a cost-efficient,high-precision technique for optimizing material performance in engineering applications. 展开更多
关键词 aluminum foam section milling cross-sectional sequence images U-Net neural network 3D model reconstruction compression simulation
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Cross-sectional study of the association between triglyceride glucose-body mass index and obstructive sleep apnea risk
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作者 Li Gong Ming Su +9 位作者 Jing-Han Xu Zhen-Fei Peng Lin Du Ze-Yao Chen Yu-Zhou Liu Lu-Cia Chan Yin-Luan Huang Yu-Tian Chen Feng-Yi Huang Chun-Li Piao 《World Journal of Diabetes》 2025年第3期65-75,共11页
BACKGROUND The triglyceride glucose-body mass index(TyG-BMI)is a novel indicator of insulin resistance(IR).Obstructive sleep apnea(OSA)is a prevalent disorder characterized by recurrent complete or partial collapse of... BACKGROUND The triglyceride glucose-body mass index(TyG-BMI)is a novel indicator of insulin resistance(IR).Obstructive sleep apnea(OSA)is a prevalent disorder characterized by recurrent complete or partial collapse of the pharyngeal airway during sleep;however,the relationship between these two conditions remains unexplored.We hypothesized that a higher TyG-BMI is associated with the occurrence of OSA.AIM To assess the association between TyG-BMI and OSA in adults in the United States.METHODS A cross-sectional study was conducted utilizing data from the National Health and Nutrition Examination Surveys spanning from 2005-2008 to 2015-2018.TyGBMI was calculated as Ln[triglyceride(mg/dL)×fasting blood glucose(mg/dL)/2]×BMI.Restricted cubic splines were used to analyze the risk of TyG-BMI and OSA occurrence.To identify potential nonlinear relationships,we combined Cox proportional hazard regression with smooth curve fitting.We also conducted sensitivity and subgroup analyses to verify the robustness of our findings.RESULTS We included 16794 participants in the final analysis.Multivariate regression analysis showed that participants with a higher TyG-BMI had a higher OSA incidence.After adjusting for all covariates,TyG-BMI was positively correlated with the prevalence of OSA(odds ratio:1.28;95%confidence interval:1.17,1.40;P<0.001);no significant nonlinear relationship was observed.Subgroup analysis showed no strong correlation between TyG-BMI and OSA in patients with diabetes.The correlation between TyG-BMI and OSA was influenced by age,sex,smoking status,marital status,hypertensive stratification,and obesity;these subgroups played a moderating role between TyGBMI and OSA.Even after adjusting for all covariates,there was a positive association between TYG-BMI and OSA prevalence.CONCLUSION A higher TyG-BMI index is linked to higher chances of developing OSA.As TyG-BMI is an indicator of IR,managing IR may help reduce the risk of OSA. 展开更多
关键词 Obstructive sleep apnea Triglyceride glucose-body mass index Insulin resistance cross-sectional National Health and Nutrition Examination Surveys
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A cross-sectional study of the association between dietary inflammatory index and glaucoma prevalence in a US population
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作者 Wen-Li Chen Li-Xia Zhang 《International Journal of Ophthalmology(English edition)》 2025年第1期139-145,共7页
AIM:To assess the relationship between dietary inflammatory index(DII)and prevalence of glaucoma among individuals aged 40y and above in the United States.METHODS:Participants were drawn from 2 cycles of the National ... AIM:To assess the relationship between dietary inflammatory index(DII)and prevalence of glaucoma among individuals aged 40y and above in the United States.METHODS:Participants were drawn from 2 cycles of the National Health and Nutrition Examination Survey(NHANES,2005-2008)for a cross-sectional study.DII was calculated from 24-hour dietary recall questionnaire conducted by experienced researchers and data analyzed in R according to the NHANES user guide,“Stratified Multi-stage Probability Sampling”.The relationship between DII and glaucoma was evaluated by multi-factor logistic regression analysis and the existence of a non-linear association examined by restricted cubic spline(RCS)analysis.RESULTS:A total of 5359 subjects were included and the cross-sectional analysis weighted to represent the US population of 109 million.DII was elevated in glaucoma patients(P<0.001)and smoking and alcohol use contributed to significant differences(P<0.001).DII correlated negatively with Healthy Eating Index(HEI)-2015(Spearman rank correlation coefficient,r=-0.49).RCS analysis showed a linear relationship between DII and glaucoma risk(P of non-linear relationship=0.575).CONCLUSION:An increased DII is strongly associated with high risk of glaucoma and diet-induced inflammation should be controlled to delay glaucoma progression. 展开更多
关键词 glaucoma risk factors dietar y inflammatory index National Health and Nutrition Examination Survey restricted cubic spline regression cross-sectional study
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基于OpenRoads Designer的桥梁下部结构设计应用研究
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作者 李昊 胡霜 《四川建材》 2026年第1期115-119,共5页
为积极推动BIM技术在我国桥梁工程领域的发展和落地应用,研究将桥梁下部结构的参数化设计与快速建模作为切入点。以Bentley平台为基础,以中国公路桥梁设计规范为依据,对OpenRoads Designer软件进行二次开发。通过分析当前桥梁建模软件... 为积极推动BIM技术在我国桥梁工程领域的发展和落地应用,研究将桥梁下部结构的参数化设计与快速建模作为切入点。以Bentley平台为基础,以中国公路桥梁设计规范为依据,对OpenRoads Designer软件进行二次开发。通过分析当前桥梁建模软件的现状及不足,系统阐述二次开发技术路线、参数化设计理念以及下部结构批量化布置方法。结合实际工程案例验证表明,该二次开发成果显著提升桥梁下部结构建模效率与准确性,为桥梁工程BIM技术的持续深化应用提供实践参考。 展开更多
关键词 BIM OpenRoads designer 二次开发 桥梁下部结构 参数化设计
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Progress in MOF-based catalyst design and reaction mechanisms for CO_(2)hydrogenation to methanol
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作者 YU Zhifu JIANG Lei WU Mingbo 《燃料化学学报(中英文)》 北大核心 2026年第1期146-162,共17页
Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon... Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon neutrality goals.The hydrogenation of CO_(2)to methanol not only enables carbon sequestration and recycling,but also provides a route to produce high value-added fuels and basic chemical feedstocks,holding significant environmental and economic potential.However,this conversion process is thermodynamically and kinetically limited,and traditional catalyst systems(e.g.,Cu/ZnO/Al_(2)O_(3))exhibit inadequate activity,selectivity,and stability under mild conditions.Therefore,the development of novel high-performance catalysts with precisely tunable structures and functionalities is imperative.Metal-organic frameworks(MOFs),as crystalline porous materials with high surface area,tunable pore structures,and diverse metal-ligand compositions,have the great potential in CO_(2)hydrogenation catalysis.Their structural design flexibility allows for the construction of well-dispersed active sites,tailored electronic environments,and enhanced metal-support interactions.This review systematically summarizes the recent advances in MOF-based and MOF-derived catalysts for CO_(2)hydrogenation to methanol,focusing on four design strategies:(1)spatial confinement and in situ construction,(2)defect engineering and ion-exchange,(3)bimetallic synergy and hybrid structure design,and(4)MOF-derived nanomaterial synthesis.These approaches significantly improve CO_(2)conversion and methanol selectivity by optimizing metal dispersion,interfacial structures,and reaction pathways.The reaction mechanism is further explored by focusing on the three main reaction pathways:the formate pathway(HCOO*),the RWGS(Reverse Water Gas Shift reaction)+CO*hydrogenation pathway,and the trans-COOH pathway.In situ spectroscopic studies and density functional theory(DFT)calculations elucidate the formation and transformation of key intermediates,as well as the roles of active sites,metal-support interfaces,oxygen vacancies,and promoters.Additionally,representative catalytic performance data for MOFbased systems are compiled and compared,demonstrating their advantages over traditional catalysts in terms of CO_(2)conversion,methanol selectivity,and space-time yield.Future perspectives for MOF-based CO_(2)hydrogenation catalysts will prioritize two main directions:structural design and mechanistic understanding.The precise construction of active sites through multi-metallic synergy,defect engineering,and interfacial electronic modulation should be made to enhance catalyst selectivity and stability.In addition,advanced in situ characterization techniques combined with theoretical modeling are essential to unravel the detailed reaction mechanisms and intermediate behaviors,thereby guiding rational catalyst design.Moreover,to enable industrial application,challenges related to thermal/hydrothermal stability,catalyst recyclability,and cost-effective large-scale synthesis must be addressed.The development of green,scalable preparation methods and the integration of MOF catalysts into practical reaction systems(e.g.,flow reactors)will be crucial for bridging the gap between laboratory research and commercial deployment.Ultimately,multi-scale structure-performance optimization and catalytic system integration will be vital for accelerating the industrialization of MOF-based CO_(2)-to-methanol technologies. 展开更多
关键词 CO_(2)hydrogenation metal-organic frameworks(MOFs) catalyst design reaction mechanism METHANOL
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Inverse design framework of hybrid honeycomb structure with high impact resistance based on active learning
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作者 Xingyu Shen Ke Yan +5 位作者 Difeng Zhu Hao Wu Shijun Luo Shaobo Qi Mengqi Yuan Xinming Qian 《Defence Technology(防务技术)》 2026年第1期407-421,共15页
In this study,an inverse design framework was established to find lightweight honeycomb structures(HCSs)with high impact resistance.The hybrid HCS,composed of re-entrant(RE)and elliptical annular re-entrant(EARE)honey... In this study,an inverse design framework was established to find lightweight honeycomb structures(HCSs)with high impact resistance.The hybrid HCS,composed of re-entrant(RE)and elliptical annular re-entrant(EARE)honeycomb cells,was created by constructing arrangement matrices to achieve structural lightweight.The machine learning(ML)framework consisted of a neural network(NN)forward regression model for predicting impact resistance and a multi-objective optimization algorithm for generating high-performance designs.The surrogate of the local design space was initially realized by establishing the NN in the small sample dataset,and the active learning strategy was used to continuously extended the local optimal design until the model converged in the global space.The results indicated that the active learning strategy significantly improved the inference capability of the NN model in unknown design domains.By guiding the iteration direction of the optimization algorithm,lightweight designs with high impact resistance were identified.The energy absorption capacity of the optimal design reached 94.98%of the EARE honeycomb,while the initial peak stress and mass decreased by 28.85%and 19.91%,respectively.Furthermore,Shapley Additive Explanations(SHAP)for global explanation of the NN indicated a strong correlation between the arrangement mode of HCS and its impact resistance.By reducing the stiffness of the cells at the top boundary of the structure,the initial impact damage sustained by the structure can be significantly improved.Overall,this study proposed a general lightweight design method for array structures under impact loads,which is beneficial for the widespread application of honeycomb-based protective structures. 展开更多
关键词 Re-entrant honeycomb Hybrid structures Inverse design Impact resistance LIGHTWEIGHT
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Advanced Design for High-Performance and AI Chips
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作者 Ying Cao Yuejiao Chen +2 位作者 Xi Fan Hong Fu Bingang Xu 《Nano-Micro Letters》 2026年第1期306-336,共31页
Recent years have witnessed transformative changes brought about by artificial intelligence(AI)techniques with billions of parameters for the realization of high accuracy,proposing high demand for the advanced and AI ... Recent years have witnessed transformative changes brought about by artificial intelligence(AI)techniques with billions of parameters for the realization of high accuracy,proposing high demand for the advanced and AI chip to solve these AI tasks efficiently and powerfully.Rapid progress has been made in the field of advanced chips recently,such as the development of photonic computing,the advancement of the quantum processors,the boost of the biomimetic chips,and so on.Designs tactics of the advanced chips can be conducted with elaborated consideration of materials,algorithms,models,architectures,and so on.Though a few reviews present the development of the chips from their unique aspects,reviews in the view of the latest design for advanced and AI chips are few.Here,the newest development is systematically reviewed in the field of advanced chips.First,background and mechanisms are summarized,and subsequently most important considerations for co-design of the software and hardware are illustrated.Next,strategies are summed up to obtain advanced and AI chips with high excellent performance by taking the important information processing steps into consideration,after which the design thought for the advanced chips in the future is proposed.Finally,some perspectives are put forward. 展开更多
关键词 Artificial intelligence Advanced chips AI chips design tactics Review and perspective
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