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Age-specific differences in the association between prediabetes and cardiovascular diseases in China:A national cross-sectional study 被引量:1
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作者 Shuo Xie Li-Ping Yu +4 位作者 Fei Chen Yao Wang Rui-Fen Deng Xue-Lian Zhang Bo Zhang 《World Journal of Diabetes》 SCIE 2024年第2期240-250,共11页
BACKGROUND Cardiovascular disease(CVD)is a leading cause of morbidity and mortality worldwide,the global burden of which is rising.It is still unclear the extent to which prediabetes contributes to the risk of CVD in ... BACKGROUND Cardiovascular disease(CVD)is a leading cause of morbidity and mortality worldwide,the global burden of which is rising.It is still unclear the extent to which prediabetes contributes to the risk of CVD in various age brackets among adults.To develop a focused screening plan and treatment for Chinese adults with prediabetes,it is crucial to identify variations in the connection between prediabetes and the risk of CVD based on age.AIM To examine the clinical features of prediabetes and identify risk factors for CVD in different age groups in China.METHODS The cross-sectional study involved a total of 46239 participants from June 2007 through May 2008.A thorough evaluation was conducted.Individuals with prediabetes were categorized into two groups based on age.Chinese atherosclerotic CVD risk prediction model was employed to evaluate the risk of developing CVD over 10 years.Random forest was established in both age groups.SHapley Additive exPlanation method prioritized the importance of features from the perspective of assessment contribution.RESULTS In total,6948 people were diagnosed with prediabetes in this study.In prediabetes,prevalences of CVD were 5(0.29%)in the younger group and 148(2.85%)in the older group.Overall,11.11%of the younger group and 29.59% of the older group were intermediate/high-risk of CVD for prediabetes without CVD based on the Prediction for ASCVD Risk in China equation in ten years.In the younger age group,the 10-year risk of CVD was found to be more closely linked to family history of CVD rather than lifestyle,whereas in the older age group,resident status was more closely linked.CONCLUSION The susceptibility to CVD is age-specific in newly diagnosed prediabetes.It is necessary to develop targeted approaches for the prevention and management of CVD in adults across various age brackets. 展开更多
关键词 Age Cardiovascular diseases PREDIABETES Risk factors differences
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Study on sex differences and potential clinical value of threedimensional computerized tomography pelvimetry in rectal cancer patients
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作者 Xiao-Cong Zhou Fei-Yue Ke +2 位作者 Gaurav Dhamija Hao Chen Qiang Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期773-786,共14页
BACKGROUND Laparoscopic rectal cancer radical surgery is a complex procedure affected by various factors.However,the existing literature lacks standardized parameters for the pelvic region and soft tissues,which hampe... BACKGROUND Laparoscopic rectal cancer radical surgery is a complex procedure affected by various factors.However,the existing literature lacks standardized parameters for the pelvic region and soft tissues,which hampers the establishment of consistent conclusions.AIM To comprehensively assess 16 pelvic and 7 soft tissue parameters through computerized tomography(CT)-based three-dimensional(3D)reconstruction,providing a strong theoretical basis to address challenges in laparoscopic rectal cancer radical surgery.METHODS We analyzed data from 218 patients who underwent radical laparoscopic surgery for rectal cancer,and utilized CT data for 3D pelvic reconstruction.Specific anatomical points were carefully marked and measured using advanced 3D modeling software.To analyze the pelvic and soft tissue parameters,we emp-loyed statistical methods including paired sample t-tests,Wilcoxon rank-sum tests,and correlation analysis.RESULTS The investigation highlighted significant sex disparities in 14 pelvic bone parameters and 3 soft tissue parameters.Males demonstrated larger measurements in pelvic depth and overall curvature,smaller measurements in pelvic width,a larger mesorectal fat area,and a larger anterior-posterior abdominal diameter.By contrast,females exhibited wider pelvises,shallower depth,smaller overall curvature,and an increased amount of subcutaneous fat tissue.However,there were no significant sex differences observed in certain parameters such as sacral curvature height,superior pubococcygeal diameter,rectal area,visceral fat area,waist circumference,and transverse abdominal diameter.CONCLUSION The reconstruction of 3D CT data enabled accurate pelvic measurements,revealing significant sex differences in both pelvic and soft tissue parameters.This study design offer potential in predicting surgical difficulties and creating personalized surgical plans for male rectal cancer patients with a potentially“difficult pelvis”,ultimately improving surgical outcomes.Further research and utilization of these parameters could lead to enhanced surgical methods and patient care in laparoscopic rectal cancer radical surgery. 展开更多
关键词 Computerized tomography Rectal cancer Three-dimensional reconstruction PELVIMETRY Sex differences
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Keep in mind sex differences when prescribing psychotropic drugs
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作者 Marianna Mazza Domenico De Berardis Giuseppe Marano 《World Journal of Psychiatry》 SCIE 2024年第2期194-198,共5页
Women represent the majority of patients with psychiatric diagnoses and also the largest users of psychotropic drugs.There are inevitable differences in efficacy,side effects and long-term treatment response between m... Women represent the majority of patients with psychiatric diagnoses and also the largest users of psychotropic drugs.There are inevitable differences in efficacy,side effects and long-term treatment response between men and women.Psychopharmacological research needs to develop adequately powered animal and human trials aimed to consider pharmacokinetics and pharmacodynamics of central nervous system drugs in both male and female subjects.Healthcare professionals have the responsibility to prescribe sex-specific psychopharmacotherapies with a priority to differentiate between men and women in order to minimize adverse drugs reactions,to maximize therapeutic effectiveness and to provide personalized management of care. 展开更多
关键词 WOMEN PSYCHOPHARMACOLOGY Psychotropic drugs Sex differences
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Three-dimensional analysis of age and sex differences in femoral head asphericity in asymptomatic hips in the United States
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作者 Mahad M Hassan Aliya G Feroe +8 位作者 Brenton W Douglass Andrew E Jimenez Benjamin Kuhns Charles F Mitchell Robert L Parisien Daniel A Maranho Eduardo N Novais Young-Jo Kim Ata M Kiapour 《World Journal of Orthopedics》 2024年第8期754-763,共10页
BACKGROUND The sphericity of the femoral head is a metric used to evaluate hip pathologies and is associated with the development of osteoarthritis and femoral-acetabular impingement.AIM To analyze the three-dimension... BACKGROUND The sphericity of the femoral head is a metric used to evaluate hip pathologies and is associated with the development of osteoarthritis and femoral-acetabular impingement.AIM To analyze the three-dimensional asphericity of the femoral head of asymptomatic pediatric hips.We hypothesized that femoral head asphericity will vary significantly between male and female pediatric hips and increase with age in both sexes.METHODS Computed tomography scans were obtained on 158 children and adolescents from a single institution in the United States(8-18 years;50%male)without hip pain.Proximal femoral measurements including the femoral head diameter,femoral head volume,residual volume,asphericity index,and local diameter difference were used to evaluate femoral head sphericity.RESULTS In both sexes,the residual volume increased by age(P<0.05).Despite significantly smaller femoral head size in older ages(>13 years)in females,there were no sex-differences in residual volume and aspherity index.There were no age-related changes in mean diameter difference in both sexes(P=0.07)with no significant sex-differences across different age groups(P=0.06).In contrast,there were significant increases in local aspherity(maximum diameter difference)across whole surface of the femoral head and all quadrants except the inferior regions in males(P=0.03).There were no sex-differences in maximum diameter difference at any regions and age group(P>0.05).Increased alpha angle was only correlated to increased mean diameter difference across overall surface of the femoral head(P=0.024).CONCLUSION There is a substantial localized asphericity in asymptomatic hips which increases with age in.While 2D measured alpha angle can capture overall asphericity of the femoral head,it may not be sensitive enough to represent regional asphericity patterns. 展开更多
关键词 HIP Femoral head SPHERICITY Skeletal growth Sex differences
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Emotional differences based on comments on doctor-patient disputes with varying levels of severity
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作者 Jing-Ru Lu Yu-Han Wei +3 位作者 Xin Wang Yu-Qing Zhang Jia-Yi Shao Jiang-Jie Sun 《World Journal of Psychiatry》 SCIE 2024年第7期1068-1079,共12页
BACKGROUND The risks associated with negative doctor-patient relationships have seriously hindered the healthy development of medical and healthcare and aroused wide-spread concern in society.The number of public comm... BACKGROUND The risks associated with negative doctor-patient relationships have seriously hindered the healthy development of medical and healthcare and aroused wide-spread concern in society.The number of public comments on doctor-patient relationship risk events reflects the degree to which the public pays attention to such events.Thirty incidents of doctor-patient disputes were collected from Weibo and TikTok,and 3655 related comments were extracted.The number of comment sentiment words was extracted,and the comment sentiment value was calculated.The Kruskal-Wallis H test was used to compare differences between each variable group at different levels of incidence.Spearman’s correlation analysis was used to examine associations between variables.Regression analysis was used to explore factors influencing scores of comments on incidents.RESULTS The study results showed that public comments on media reports of doctor-patient disputes at all levels are mainly dominated by“good”and“disgust”emotional states.There was a significant difference in the comment scores and the number of partial emotion words between comments on varying levels of severity of doctor-patient disputes.The comment score was positively correlated with the number of emotion words related to positive,good,and happy)and negatively correlated with the number of emotion words related to negative,anger,disgust,fear,and sadness.CONCLUSION The number of emotion words related to negative,anger,disgust,fear,and sadness directly influences comment scores,and the severity of the incident level indirectly influences comment scores. 展开更多
关键词 Doctor-patient relationship Doctor-patient dispute COMMENTS Emotional differences Weibo TikTok
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Temporal and spatial differences in human activities performed in Urban Green Spaces of Vilnius(Lithuania)
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作者 Luís Valença Pinto Carla Sofia Santos Ferreira Paulo Pereira 《Geography and Sustainability》 CSCD 2024年第2期302-317,共16页
Urban green spaces(UGS)are relevant to city well-being,as recognized by the United Nations’Sustainable Development Goals(SDGs).However,few studies have studied the temporal use of UGS.This work assessed the seasonal,... Urban green spaces(UGS)are relevant to city well-being,as recognized by the United Nations’Sustainable Development Goals(SDGs).However,few studies have studied the temporal use of UGS.This work assessed the seasonal,weekly,and daily use of three urban green spaces(Vingis Park,Bernardino Garden,and Jomantas Park)in Vilnius(Lithuania).The study is based on an on-site observation-based survey,which recorded users’characteristics,activities,and weather conditions during summer and winter.The results showed that UGS’s seasonal,weekly,and daily use differed according to park and users’characteristics.Parks with a higher diversity of facilities had a high seasonal difference in the number of observed activities.User numbers were higher in the summer for activities with children,social activities,sports,and water activities than in the winter.Jomantas Park had the lowest variability in user characteristics.Weather variables were linked to changes in users’activities.Higher precipitation and lower temperature were associated with reducing the number of users and the diversity of registered activities.Most of the stationary activities were observed during summer.The diversity of the observed activities was associated with the available facilities rather than the park size.The distribution of stationary activities was spatially correlated with facility/equipment(benches,playgrounds,sports,and fitness equipment)and proximity to water features.The results of this study are relevant for UGS design,planning,and management. 展开更多
关键词 Urban parks Seasonal differences Temporal use Time of day Spatial distribution of UGS users
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Exploring Phonetic Differences and Cross-Linguistic Influences: A Comparative Study of English and Mandarin Chinese Pronunciation Patterns
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作者 Than My Thi Duyen 《Open Journal of Applied Sciences》 2024年第7期1807-1822,共16页
Exploring the differences in phonemes and cross-linguistic influences, particularly by comparing the pronunciation patterns of English and Mandarin, is crucial for language learners. Such comparative studies can help ... Exploring the differences in phonemes and cross-linguistic influences, particularly by comparing the pronunciation patterns of English and Mandarin, is crucial for language learners. Such comparative studies can help learners better understand and overcome the pronunciation difficulties encountered during second language acquisition. English and Mandarin have significant differences in their vowel and consonant systems, tones, intonation, and syllable structures. A deep understanding of these differences allows learners to engage in targeted pronunciation training, reducing accent interference. This research provides guidance for improving language teaching methods, enabling teachers to design more effective pronunciation strategies and exercises based on the students’ native language backgrounds, thus enhancing learning outcomes. Additionally, cross-linguistic studies aid in improving speech recognition and conversion technologies, achieving higher accuracy and naturalness in multilingual speech processing systems. From a cultural exchange perspective, understanding and respecting the phonetic characteristics of different languages help to enhance the effectiveness and mutual understanding in cross-cultural communication. The comparative study of English and Mandarin pronunciation patterns not only provides a theoretical foundation for language education and technological applications but also promotes effective communication in multilingual environments. This thesis uses a comparative research method to elucidate the study of English and Mandarin pronunciation patterns. It begins with an analysis of the characteristics and similarities of the pronunciation patterns in both languages. The thesis then examines the differences between English and Mandarin pronunciation patterns through four aspects: the number and complexity of vowel phonemes, types and distribution of consonant phonemes, tones and stress, and intonation and phonetic phenomena. Finally, based on the comparative analysis of the differences, the thesis offers targeted policy recommendations for learning English and Mandarin. 展开更多
关键词 ENGLISH MANDARIN Pronunciation Patterns Phoneme differences
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Interhemispheric and longitudinal differences in the ionosphere-thermosphere coupling process during the May 2024 superstorm
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作者 WenBo Li LiBo Liu +5 位作者 YuYan Yang TingWei Han RongJin Du RuiLong Zhang HuiJun Le YiDing Chen 《Earth and Planetary Physics》 EI CAS CSCD 2024年第6期910-919,共10页
Geomagnetic storm events have a strong influence on the ionosphere–thermosphere(I-T)coupling system.Analyzing the regional response process of the I-T system and its differences across the northern and southern hemis... Geomagnetic storm events have a strong influence on the ionosphere–thermosphere(I-T)coupling system.Analyzing the regional response process of the I-T system and its differences across the northern and southern hemispheres is an important but challenging task.In this study,we used a combination of multiple observations and a model simulation to examine the north–south hemispheric difference in the I-T coupling system in the American and Asian sectors during the geomagnetic superstorm that occurred in May 2024.Observations of the total electron content(TEC)showed that the Asian sector had negative storms in the northern hemisphere and positive storms in the southern hemisphere,a process that exacerbated the hemispheric differences in the TEC.However,both hemispheres of the American sector showed negative storms.The thermospheric composition changes also differed between the two sectors,and their variation could partially explain the hemispheric differences caused by positive and negative storms.Moreover,the influence of the thermospheric density change was less than that of the thermospheric composition.Finally,the dynamic effect of the thermospheric wind and the plasma transport processes strongly modulated the north–south differences in the TEC at nighttime in the American and Asian sectors,respectively,during this superstorm. 展开更多
关键词 geomagnetic superstorm north–south hemispheric difference total electron content O/N2 thermospheric wind plasma transport
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Sex differences in the association between the muscle quality index and the incidence of depression: A cross-sectional study
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作者 Gui-Ping Huang Li-Ping Mai +2 位作者 Zhi-Jie Zheng Xi-Pei Wang Guo-Dong He 《World Journal of Psychiatry》 SCIE 2024年第9期1335-1345,共11页
BACKGROUND Depression presents significant challenges to mental health care.Although phy-sical activity is highly beneficial to mental and physical health,relatively few stu-dies have conducted on the relationship bet... BACKGROUND Depression presents significant challenges to mental health care.Although phy-sical activity is highly beneficial to mental and physical health,relatively few stu-dies have conducted on the relationship between them.AIM To investigate the association between muscle quality index(MQI)and incidence of depression.METHODS The data used in this cross-sectional study were obtained from the 2011-2014 National Health and Nutritional Examination Survey,which included informa-tion on MQI,depression,and confounding factors.Multivariable logistic regre-ssion models were employed,while taking into account the complex multi-stage sampling design.A restricted cubic spline model was utilized to investigate the non-linear relationship between the MQI and depression.Additionally,subgroup analyses were performed to identify influential factors.RESULTS The prevalence of depression in this population was 8.44%.With the adjusted model,the MQI was associated with depression in females(odds ratio=0.68,95%confidence interval:0.49-0.95)but not in males(odds ratio=1.08,95%confidence interval:0.77-1.52).Restricted cubic spline adjustment of all covariates showed a significant negative non-linear relationship between depression and the MQI in females.The observed trend indicated an 80%decrease in the risk of depression for each unit increase in MQI,until a value of 2.2.Subsequently,when the MQI exceeded 2.2,the prevalence of depression increased by 20%for every unit increase in the MQI.Subgroup analyses further confirmed that the MQI was negatively associated with de-pression.CONCLUSION The MQI was inversely correlated with depression in females but not males,suggesting that females with a higher MQI might decrease the risk of depression. 展开更多
关键词 Sex differences Muscle quality index DEPRESSION National Health and Nutrition Examination Survey Population-based study
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Model of Mediating Determinants of Time Differences in INDYCAR
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作者 Wilfrido Isidro Aldana Balderas Héctor Daniel Molina Ruiz +5 位作者 Enrique Martínez Muñoz Eleazar Villegas González Tirso Javier Hernández Gracia Arturo Sánchez Sánchez Cruz García Lirios Alfredo Barrera Escobar 《Journalism and Mass Communication》 2024年第4期232-240,共9页
The IndyCar series distinguishes itself by providing the same design and operation of the single-seater to its pilots.The difference in times is then attributable to the skills of the drivers,but considering the data ... The IndyCar series distinguishes itself by providing the same design and operation of the single-seater to its pilots.The difference in times is then attributable to the skills of the drivers,but considering the data from the races could test this assumption.The objective of this work was to establish a trajectory model to predict race times.A cross-sectional,correlational,and explanatory work was carried out with a sample of 18,474 records in the period from 2020 to 2023 of the IndyCar series.The results show that the time span predicts the time differences.In relation to the studies of acceptance of the technology,the adjustment of this to human capacities to explain the time differences in the series of racing cars is discussed. 展开更多
关键词 time differences ranking differences RANKING race time laps completed
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A Comprehensive Study on Gender Language and Its Differences in China
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作者 Suofeiya Fan 《Journal of Contemporary Educational Research》 2024年第7期187-191,共5页
The study of language and gender,especially the study of gender language differences involves many fields such as psychology,sociology,anthropology,language and literature,news media,education,and so on.Starting from ... The study of language and gender,especially the study of gender language differences involves many fields such as psychology,sociology,anthropology,language and literature,news media,education,and so on.Starting from the broad definition of gender language,this paper composes and reviews the research history of domestic gender language and its differences.Around the research history of domestic gender language,the research period is divided according to the timeline into germination,genesis,and growth.Divided by theme and content,the main content is the phenomenon of sexism in language;the second is the study of gender language style differences;the third is the root causes of sexism and verbal gender differences,i.e.,the construction of the corresponding theories;and the fourth is the discussion of the limitations of the study of gender language in foreign countries. 展开更多
关键词 Language and gender Gender language differences Language differences
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Analyzing the Differences in the Concepts of Love Between Korean and American Women Using the Female Characters in Kim Ji-young,Born in 1982 and The Sun Also Rises as Examples
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作者 Xiaoyi Yang 《Journal of Contemporary Educational Research》 2024年第2期112-116,共5页
This paper scrutinizes the differences in the conceptualization of love between Korean and American women.Grounded in an analysis of literary figures,Brett and Kim Ji-young,the study unravels the intricate interplay o... This paper scrutinizes the differences in the conceptualization of love between Korean and American women.Grounded in an analysis of literary figures,Brett and Kim Ji-young,the study unravels the intricate interplay of cultural,historical,and societal forces shaping these perspectives.The contrasting landscapes of the United States,driven by ideals of freedom and individualism,and Korea,entrenched in Confucian values and collectivism,serve as crucibles for forming women’s roles,self-perception,and societal expectations.The examination extends to communication styles,illuminating the directness of American expression versus Korea’s reliance on formalism.Through this exploration,the paper illustrates the profound impact of cultural contexts on the intricate tapestry of love,offering a nuanced understanding of divergent viewpoints within a global context. 展开更多
关键词 LOVE Cultural differences Women Society INDIVIDUALISM
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The Impact of Urban and Rural Education Gap on Student Achievement Differences
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作者 Weiping Fu Abdul Talib bin Mohamed Hashim 《Journal of Contemporary Educational Research》 2024年第9期145-150,共6页
With our country’s social development,the gap between urban and rural education has become increasingly obvious,especially the difference in student achievement.This study aims to explore the impact of the urban-rura... With our country’s social development,the gap between urban and rural education has become increasingly obvious,especially the difference in student achievement.This study aims to explore the impact of the urban-rural education gap on student achievement.The study adopts a quantitative analysis method to collect and analyze the academic performance,learning resources,and social resources of urban and rural students.The results show that the unbalanced distribution of educational resources in urban and rural areas is the key factor leading to the gap in students’achievement.For example,urban education resources are abundant while rural education resources are relatively scarce.At the same time,the difference in social environment and family economic status also have a significant impact on student achievement.The differences between urban and rural areas,particularly in terms of family economic conditions and their ability to invest in education,further widen the gap between urban and rural education.The results of this study can provide a reference for reducing the gap between urban and rural education and improving the academic performance of rural students.A fair education policy is essential to narrow the gap between urban and rural education resources distribution,so as to improve the equality of education in society. 展开更多
关键词 Urban and rural education gap Student achievement differences Allocation of educational resources Social and environmental differences Family economic situation
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Discussion on the Differences between Chinese and Western Cultures and Intercultural Translation
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作者 Lin Yuan 《Journal of Contemporary Educational Research》 2024年第10期178-184,共7页
Due to different geographical backgrounds and development histories,there are certain cultural differences between China and Western countries,which often lead to cultural conflicts and seriously affect the efficiency... Due to different geographical backgrounds and development histories,there are certain cultural differences between China and Western countries,which often lead to cultural conflicts and seriously affect the efficiency and effectiveness of cultural exchanges.In the context of accelerating economic globalization and integration,as well as increasing cooperation among countries,in order to ensure the accuracy of translation,it is necessary to have a proficient and accurate understanding of the cultural differences between China and the West.By relying on these cultural differences,we can improve communication patterns and continuously enhance intercultural translation skills. 展开更多
关键词 Cultural differences Intercultural translation Skill enhancement
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Comparative Analysis of Differences among Northern,Jiangnan,and Lingnan Classical Private Gardens Using Principal Component Cluster Method
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作者 Lijuan Sun Hui Wang 《Journal of Architectural Research and Development》 2024年第5期20-29,共10页
This paper investigates the design essence of Chinese classical private gardens,integrating their design elements and fundamental principles.It systematically analyzes the unique characteristics and differences among ... This paper investigates the design essence of Chinese classical private gardens,integrating their design elements and fundamental principles.It systematically analyzes the unique characteristics and differences among classical private gardens in the Northern,Jiangnan,and Lingnan regions.The study examines nine classical private gardens from Northern China,Jiangnan,and Lingnan by utilizing the advanced tool of principal component cluster analysis.Based on literature analysis and field research,273 variables were selected for principal component analysis,from which four components with higher contribution rates were chosen for further study.Subsequently,we employed clustering analysis techniques to compare the differences among the three types of gardens.The results reveal that the first principal component effectively highlights the differences between Jiangnan and Lingnan private gardens.The second principal component serves as the key to defining the types of Northern private gardens and distinguishing them from the other two types,and the third principal component indicates that Lingnan private gardens can be categorized into two distinct types as well. 展开更多
关键词 Classical gardens Private gardens differences Principal component analysis Cluster analysis
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无位置传感器的SRD调速系统的初始位置检测 被引量:13
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作者 杨波 曹家勇 +1 位作者 陈幼平 周祖德 《中国电机工程学报》 EI CSCD 北大核心 2002年第12期101-105,共5页
该文基于对SRM线性电感模型和连续两相电磁特性进行分析的基础上,探讨了转子处于静止和有初始转动两种状态下,转子初始位置检测及初始导通相的确定方法,通过对6/4极的三相开关磁阻电机的实验,验证了该方法的可行性。
关键词 无位置传感器 srd 调速系统 初始位置检测 开关磁阻电机 线性电感模型
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用VHDL设计的SRD模糊控制器 被引量:2
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作者 郭爱琴 周百新 《南京师范大学学报(工程技术版)》 CAS 2004年第1期38-41,共4页
用硬件描述语言VHDL对SR电动机比例因子自调整模糊控制器进行了数字设计 ,并用FPGA加以实现 ,制成了高可靠性的单片SRD控制电路 .实验表明 :用VHDL设计的SRD模糊控制器不仅可靠性高 ,而且还支持众多的硬件模型 。
关键词 srd 数字化设计 VHDL语言 模湖控制器 FPGA 开关磁组电动机调速系统
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一种基于SRD和NLTL的皮秒级脉冲产生电路 被引量:6
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作者 周建明 高晓薇 +2 位作者 陈宁 郭德纯 费元春 《固体电子学研究与进展》 CAS CSCD 北大核心 2007年第1期40-43,73,共5页
提出了一种利用SRD产生窄脉冲信号的方法,对其产生窄脉冲的机理进行了分析和仿真,为了使得脉冲宽度变得更窄,电路采用了NLTL结构,拓展了SRD产生窄脉冲的应用,文中分析了NLTL的工作原理。设计了基于SRD和NLTL的皮秒级脉冲产生电路,给出... 提出了一种利用SRD产生窄脉冲信号的方法,对其产生窄脉冲的机理进行了分析和仿真,为了使得脉冲宽度变得更窄,电路采用了NLTL结构,拓展了SRD产生窄脉冲的应用,文中分析了NLTL的工作原理。设计了基于SRD和NLTL的皮秒级脉冲产生电路,给出了测试结果,脉冲宽度为110 ps,幅度为3 V。 展开更多
关键词 阶跃恢复二极管 非线性传输线 窄脉冲 超宽带
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SRD5A1基因多态性与寻常型痤疮易感性关系的研究 被引量:3
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作者 蔡丽敏 李晓庆 +4 位作者 陈翠 杨晶 张金芝 王燕华 刘静 《哈尔滨医科大学学报》 CAS 2017年第2期148-152,共5页
目的探讨SRD5A1基因的单核苷酸多态性与汉族人群寻常型痤疮的遗传易感性之间的相关性。方法从378例寻常痤疮患者和200名健康受试者的外周血分离基因组DNA。设计特异性引物,对SRD5A1基因的5个外显子进行PCR扩增并行DNA测序。结果在SRD5A... 目的探讨SRD5A1基因的单核苷酸多态性与汉族人群寻常型痤疮的遗传易感性之间的相关性。方法从378例寻常痤疮患者和200名健康受试者的外周血分离基因组DNA。设计特异性引物,对SRD5A1基因的5个外显子进行PCR扩增并行DNA测序。结果在SRD5A1基因的5个外显子共发现4个单核苷酸基因多态性位点,分别为rs248793,rs3822430,rs8192186和rs3736316。rs8192186和rs3736316在重型痤疮组和对照组及轻型痤疮组中等位基因频率和基因型频率有显著差异,在重型痤疮组呈现频率更高的等位基因G和GG基因型。此外,rs3822430在重型痤疮组不存在GG基因型,rs8192186和rs3736316不存在AA基因型。结论 rs8192186和rs3736316两个同义的单核苷酸多态性可能在SRD5A1的表达和对重型痤疮的易感性上具有潜在的作用。rs3822430具有GG基因型或rs8192186及rs3736316具有AA基因型的患者可能具有患重型痤疮更低的风险。 展开更多
关键词 srd5A1 基因多态性 易感性 寻常型痤疮
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基于模糊自适应PID控制的SRD研究 被引量:1
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作者 钟坤炎 易灵芝 《湖南工业大学学报》 2008年第5期28-31,共4页
分析开关磁阻电动机驱动系统(SRD)的结构与总体控制方案;分析开关磁阻电动机非线性数学模型;分析模糊自适应PID控制的原理。在Matlab/Simulink中建立基于模糊自适应PID控制的SRD动态仿真模型,仿真结果证明:基于模糊自适应PID控制的SRD... 分析开关磁阻电动机驱动系统(SRD)的结构与总体控制方案;分析开关磁阻电动机非线性数学模型;分析模糊自适应PID控制的原理。在Matlab/Simulink中建立基于模糊自适应PID控制的SRD动态仿真模型,仿真结果证明:基于模糊自适应PID控制的SRD能明显减小转速超调和转矩脉动,提高系统鲁棒性,得到更好的动态性能。 展开更多
关键词 模糊自适应 PID srd 仿真
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