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基础教育数字化转型的国际动态研究——以日本GIGA School构想为例 被引量:1
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作者 张文超 《教育教学论坛》 2024年第1期29-32,共4页
教育数字化转型已成为国际热议话题,国际上各国成效显著的基础教育数字化转型政策与行动对解决我国基础教育数字化转型中的问题有借鉴意义。近年来日本通过GIGA School构想的实践正逐步实现一人一台电子终端的基础教育数字化转型。因此... 教育数字化转型已成为国际热议话题,国际上各国成效显著的基础教育数字化转型政策与行动对解决我国基础教育数字化转型中的问题有借鉴意义。近年来日本通过GIGA School构想的实践正逐步实现一人一台电子终端的基础教育数字化转型。因此,尝试从日本的相关政策中解析其转型目的以及落实措施,并提出细化教育数字化转型目标、明确教育数字化转型标准、搭建转型建设体系、构建多方面政策联动系统的实践启示。 展开更多
关键词 基础教育 数字化转型 日本GIGA school构想
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Adolescent suicide risk factors and the integration of socialemotional skills in school-based prevention programs 被引量:2
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作者 Xin-Qiao Liu Xin Wang 《World Journal of Psychiatry》 SCIE 2024年第4期494-506,共13页
Adolescents are considered one of the most vulnerable groups affected by suicide.Rapid changes in adolescents’physical and mental states,as well as in their lives,significantly and undeniably increase the risk of sui... Adolescents are considered one of the most vulnerable groups affected by suicide.Rapid changes in adolescents’physical and mental states,as well as in their lives,significantly and undeniably increase the risk of suicide.Psychological,social,family,individual,and environmental factors are important risk factors for suicidal behavior among teenagers and may contribute to suicide risk through various direct,indirect,or combined pathways.Social-emotional learning is considered a powerful intervention measure for addressing the crisis of adolescent suicide.When deliberately cultivated,fostered,and enhanced,selfawareness,self-management,social awareness,interpersonal skills,and responsible decision-making,as the five core competencies of social-emotional learning,can be used to effectively target various risk factors for adolescent suicide and provide necessary mental and interpersonal support.Among numerous suicide intervention methods,school-based interventions based on social-emotional competence have shown great potential in preventing and addressing suicide risk factors in adolescents.The characteristics of school-based interventions based on social-emotional competence,including their appropriateness,necessity,cost-effectiveness,comprehensiveness,and effectiveness,make these interventions an important means of addressing the crisis of adolescent suicide.To further determine the potential of school-based interventions based on social-emotional competence and better address the issue of adolescent suicide,additional financial support should be provided,the combination of socialemotional learning and other suicide prevention programs within schools should be fully leveraged,and cooperation between schools and families,society,and other environments should be maximized.These efforts should be considered future research directions. 展开更多
关键词 Adolescent suicide Risk factors Social-emotional skills Social and emotional learning school Prevention
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A Survey of Digital Content Required for STD Prevention Education Taught by School Nurses
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作者 Tomoko Nakamura 《Health》 2024年第4期350-370,共21页
Purpose: In recent years, there has been concern in Japan about the increase in STDs among adolescents aged 15 - 19. In order to prevent STDs and guide adolescents toward desirable sexual behavior, this study’s goal ... Purpose: In recent years, there has been concern in Japan about the increase in STDs among adolescents aged 15 - 19. In order to prevent STDs and guide adolescents toward desirable sexual behavior, this study’s goal was to examine the actual state of STD prevention education taught by school nurses as part of the school curriculum, as well as the kinds of digital content they wish to have for teaching on the subject. Method: An anonymous, self-administered questionnaire was distributed by email and leaflet. Targeting the 100 valid responses received from the surveyed school nurses, descriptive statistics were made for each survey item and comparisons were made between the early- and mid-career groups based on years of experience. Results: 70.0% of respondents reported teaching about STDs in Health & Physical Education classes. School nurses in the early-career group used ready-made materials, while the mid-career group used both ready-made and self-made materials. 95% of respondents reported that they had little or no knowledge of STDs, while 84% reported that they were “good” or “fairly good” at teaching classes on sexuality. Both groups reported difficulty with the topics of “phimosis” and “nocturnal emissions” in the physiological category, “sexual behavior” in the “sex-adjacent” category, and “sexual and reproductive issues” in the psychosocial category. Respondents expressed a need for digital content covering the topics of “sexual violence”, “sexual abuse”, “sexually transmitted diseases”, and “how to turn down sex”. The mid-career group desired digital content for more items than the early-career group, with significant differences in the pathogens involved in sexually transmitted diseases and sex-adjacent items. 32.0% of respondents answered that they had done self-study for sex education classes in the past three years, and both groups desired self-study on “sexually transmitted diseases”, with the mid-career group significantly higher than the early-career group on “cervical cancer & HPV”, “emergency contraceptives”, and “media literacy”. Conclusion: Health & Physical Education is the main subject that covers STDs, and pre-existing materials are commonly used. It is expected that this is due to nurses’ busy schedules and the fact that only one school nurse is assigned to each school. The data collected suggested that nurse teachers want categorized digital content that can be used in the classes they are responsible for, rather than educational content on topics they are not comfortable with. In addition, given the changing environment surrounding sex, it was clear that they wish to understand the realities and needs of the high school students they teach, and desire self-study opportunities to improve their teaching methods. 展开更多
关键词 High school Students Sexually Transmitted Diseases Digital Content school Nurses
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Impact of School Canteens on School Retention and Academic Performance in the Atlantic Department (Benin)
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作者 Mahunan Léocadie Akpoli Gbèssohèlè Justin Behanzin +1 位作者 Christophe Chabi Alphonse Sezan 《Food and Nutrition Sciences》 CAS 2024年第9期869-879,共11页
In Benin, obstacles to universal access to primary education persist. In rural areas, enrolment and attendance rates remain low due to several factors. Families living in poverty may not be able to afford to send thei... In Benin, obstacles to universal access to primary education persist. In rural areas, enrolment and attendance rates remain low due to several factors. Families living in poverty may not be able to afford to send their children to school;although the government has eliminated primary school fees, parents still have to buy school uniforms and supplies. There is also an opportunity cost associated with sending girls to school, rather than keeping them at home where they can help their mothers with household chores and look after their younger siblings (School canteens in Benin to improve student enrolment and retention in partnership with parents’ associations, 2008). Prior to 2016, the school feeding system was in its infancy, with canteens operated for only three months of the year. However, thanks to determined government reforms, the school canteen system has undergone a profound transformation. The implementation of a USD 79 million has not only not only increased coverage from coverage from 30% to 75% today, but also set the ambitious target ambitious goal of achieving 100% coverage by the end of 2023 [1]. The aim of this study is to assess the impact of canteens on school retention and children’s academic performance. We conducted a descriptive and analytical diagnostic survey using a questionnaire designed for parents of schoolchildren. Canteens increase and maintain the number of children in our schools, especially when the providers start their activities, in this case those traveling long distances. Almost all the parents surveyed believe that the school canteen has had an impact on their children’s motivation to attend school and class, and consequently on their performance. For example, for all parents surveyed, the school canteen has reduced the risk of children dropping out of school, especially girls (97%), although the difference with boys (95%) remains small and is not statistically significant. What’s more, since the advent of the PNASI, in the Atlantic department, the CEP pass rate in schools with canteens far exceeds that of schools without canteens. This shows that canteens play a major and positive role in the retention and success of the schoolchildren who benefit from them. 展开更多
关键词 school Canteens IMPACT ATLANTIC Pnasi BENIN
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Floating periodic pontoons for broad bandgaps of water waves
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作者 Huaqing JIN Haicheng ZHANG +1 位作者 Ye LU Daolin XU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第11期1913-1928,共16页
The narrow attenuation bands of traditional marine structures have long been a challenge in mitigating water waves.In this paper,a metastructure(MS)composed of floating periodic pontoons is proposed for broadband wate... The narrow attenuation bands of traditional marine structures have long been a challenge in mitigating water waves.In this paper,a metastructure(MS)composed of floating periodic pontoons is proposed for broadband water wave attenuation.The interaction of surface gravity waves with the MS is investigated using linear wave theory.The potential solutions of water waves by the MS with a finite array are developed by using the eigenfunction expansion matching method(EEMM),and the band structure of the MS is calculated by the transfer matrix method(TMM),in which the evanescent modes of waves are considered.The solution is verified against the existing numerical result for a special case.Based on the present solution,the association between Bragg resonance reflection and Bloch bandgaps is examined,the effects of pontoon geometry are analyzed,and the comparison between floating MS and bottom-mounted periodic structures is conducted.A computational fluid dynamics(CFD)model is further developed to assess the structures in practical fluid environments,and the floating MS presents excellent wave attenuation performance.The study presented here may provide a promising solution for protecting the coast and offshore structures. 展开更多
关键词 floating metastructure(MS) wave attenuation bandgap analytical method
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Are school uniforms associated with gender inequalities in physical activity? A pooled analysis of population-level data from 135 countries/regions
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作者 Mairead Ryan Luiza I.C.Ricardo +2 位作者 Nicole Nathan Riikka Hofmann Esther van Sluijs 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第4期590-598,共9页
Purpose:It is aimed to assess whether school uniforms are associated with population-level gender inequalities in physical activity,and whether associations differ by school level,country/region income,and assessment ... Purpose:It is aimed to assess whether school uniforms are associated with population-level gender inequalities in physical activity,and whether associations differ by school level,country/region income,and assessment method.Methods:An ecological study design was employed.We collected data about global uniform practices using an online survey.We searched for country/region-level estimates of school-aged youth meeting physical activity guidelines from international surveillance studies.Study selection was conducted in duplicate using a systematic process,and a random sample of all data was checked to ensure extraction and pooling processes were accurate.We calculated absolute and relative gender inequalities in physical activity for each country.Linear regression examined associations between country/region-level uniform practices(binary yes/no exposure variable) and country/region-level gender inequalities in physical activity guideline compliance(absolute and relative inequalities).We investigated moderation by school level,stratified analyses by income group,and repeated primary analyses using device-measured data.Results:Pooling data from 135 countries/regions(n=1,089,852),we found no association between population-level uniform practices and gender inequalities in physical activity across all ages(absolute:β=-0.2;95% confidence interval(95%CI):-1.7 to 1.3,p=0.74;relative:β=0.1;95%CI:-0.1 to 0.2,p=0.51).Subgroup analysis suggested a positive association in primary school settings(absolute:β=4.3;95%CI:-0.0 to 8.6,p=0.05).Among high-income countries,absolute inequalities were significantly greater in countries/regions with uniform practices(N=37) compared to those without(N=48)(9.1(SD=3.6) vs.7.8 percentage points(SD=4.3)).Repeating analyses using device-measured data(n=32,130;N=24) did not alter our primary finding.From initial descriptive statistics,we found that in countries/regions where a maj ority of schools(>50%) reportedly use uniforms,there was lower compliance with physical activity guidelines among all genders(median:16.0%,interquartile range:13.2%-19.9%,N=103) compared to generally non-uniform countries/regions(median:19.5%,interquartile range:16.4%-23.5 %,N=32)(z=3.04,p=0.002).(N=countries,regions and studies repre sented;n=sample size or participants included).Conclusion:School uniforms are associated with greater gender inequalities in physical activity in primary school settings and in high-income countries.Our population-level findings warrant testing using individual-level data across contexts. 展开更多
关键词 school policy CLOTHING Child ADOLESCENT ACCELEROMETER
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Characterization of Wastewater in School Environments for an Ecological Treatment Solution: A Case Study of Ndiebene Gandiol 1 School
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作者 Falilou Coundoul Abdou Khafor Ndiaye Abdoulaye Deme 《Journal of Water Resource and Protection》 CAS 2024年第1期27-40,共14页
The study conducted at Ndiebene Gandiol 1 school in Senegal has unveiled serious environmental and public health challenges. The wastewater analysis revealed high levels of Biochemical Oxygen Demand (BOD5), Chemical O... The study conducted at Ndiebene Gandiol 1 school in Senegal has unveiled serious environmental and public health challenges. The wastewater analysis revealed high levels of Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), and fecal coliforms, signaling potential risks to the well-being of students and staff. This situation mirrors a wider issue in rural educational settings, where inadequate sanitation persists. Intensive wastewater treatment options are known for their effectiveness against high pollutant loads but are resource-intensive in both energy and cost. Conversely, extensive treatment systems, while requiring more land, provide a sustainable alternative by harnessing natural processes for pollutant removal. The research suggests a hybrid treatment approach could serve the school’s needs, balancing the robust capabilities of intensive methods with the ecological benefits of extensive systems. Such a solution would need to be tailored to the specific environmental, financial, and logistical context of the school, based on comprehensive feasibility studies and stakeholder engagement. This study’s findings underscore the urgency of addressing sanitation in schools, as it is intrinsically linked to the health and academic success of students. Quick, effective, and long-term strategies are vital to secure a healthier and more prosperous future for the youth. With proper implementation, the school can transform its sanitation facilities, setting a precedent for rural educational institutions in Senegal and similar contexts globally. 展开更多
关键词 Wastewater Characterization Ecological Treatment school Sanitation PHYTOREMEDIATION Rural Infrastructure Environmental Health
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Migration Networks Pattern of China’s Floating Population from the Perspective of Complex Network
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作者 LIU Wangbao CHEN Ranran 《Chinese Geographical Science》 SCIE CSCD 2024年第2期327-341,共15页
Since China’s reform and opening-up,the growing disparity between urban and rural areas and regions has led to massive migration.With China’s Rural Revitalization Strategy and the industrial transfer from the easter... Since China’s reform and opening-up,the growing disparity between urban and rural areas and regions has led to massive migration.With China’s Rural Revitalization Strategy and the industrial transfer from the eastern coastal areas to the inland,the migration direction and pattern of the floating population have undergone certain changes.Using the 2017 China Migrants Dynamic Survey(CMDS),excluding Hong Kong,Macao,and Taiwan regions of China,organized by China’s National Health Commission,the relationship matrix of the floating population is constructed according to the inflow place of the interviewees and their outflow place(the location of the registered residence)in the questionnaire survey.We then apply the complex network model to analyze the migration direction and network pattern of China’s floating population from the city scale.The migration network shows an obvious hierarchical agglomeration.The first-,second-,third-and fourth-tier distribution cities are municipalities directly under the central government,provincial capital cities,major cities in the central and western regions and ordinary cities in all provinces,respectively.The migration trend is from the central and western regions to the eastern coastal areas.The migration network has‘small world’characteristics,forming nine communities.It shows that most node cities in the same community are closely linked and geographically close,indicating that the migration network of floating population is still affected by geographical proximity.Narrowing the urban-rural and regional differences will promote the rational distribution this population.It is necessary to strengthen the reform of the registered residence system,so that the floating population can enjoy urban public services comparable to other populations,and allow migrants to live and work in peace. 展开更多
关键词 complex network floating population migration network spatial pattern community structure
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Global Dynamic Responses and Progressive Failure of Submerged Floating Tunnel Under Cable Breakage Conditions
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作者 ZHOU Xiang-bo QIAO Dong-sheng +3 位作者 WANG Ming TANG Guo-qiang LU Lin OU Jinping 《China Ocean Engineering》 SCIE EI CSCD 2024年第4期676-688,共13页
The Submerged Floating Tunnel(SFT)relies on a tensioned mooring system for precise positioning.The sudden breakage of a single cable can trigger an immediate alteration in the constraint conditions of the tube,inducin... The Submerged Floating Tunnel(SFT)relies on a tensioned mooring system for precise positioning.The sudden breakage of a single cable can trigger an immediate alteration in the constraint conditions of the tube,inducing a transient heave response within the structure along with a transient increase in cable tension experienced by adjacent cables.In more severe cases,this may even lead to a progressive failure culminating in the global destruction of the SFT.This study used ANSYS/AQWA to establish a numerical model of the entire length SFT for the hydrodynamic response analysis,and conducted a coupled calculation of the dynamic responses of the SFT-mooring line model based on Orca Flex to study the global dynamic responses of the SFT at the moment of cable breakage and the redistribution of cable internal forces.The most unfavorable position for SFT cable breakage was identified,the influence mechanism of cable breakage at different positions on the global dynamic response was revealed,and the progressive chain failure pattern caused by localized cable breakage are also clarified. 展开更多
关键词 submerged floating tunnel cable breakage global dynamic responses progressive failure
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Simulation of wave scattering over a floating platform in the ocean with a coupled CFD-IBM model
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作者 Pengxuan Luo Jingxin Zhang +1 位作者 Yongyong Cao Shaohong Song 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第3期157-161,共5页
A numerical study of linear wave scattering over a floating platform has been simulated by an efficient numericalmodel in this letter.The non-hydrostatic model is used to simulate the free surface and the uneven botto... A numerical study of linear wave scattering over a floating platform has been simulated by an efficient numericalmodel in this letter.The non-hydrostatic model is used to simulate the free surface and the uneven bottom.For thesolid body modelling,the immersed boundary method(IBM)is implemented by introducing a virtual boundaryforce into the momentum equations to emulate the boundary conditions.This implementation enhances theability of the model to simulate interactions between waves and floating structures.A numerical case involvingwave interactions with a floating platform is studied to validate the numerical model.By simulating the wavepropagation,the numerical model captures the variation of the wave scattering very well,which verifies theperformance of the numerical model and the robust strategy of the IBM. 展开更多
关键词 Non-hydrostatic model Immersed boundary method Wave structure interaction floating platform
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Experimental Study on Hydrodynamic Load Characteristics for A Typical Cross-Section of A Submerged Floating Tunnel
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作者 ZHANG Hong-qian YANG Zhi-wen +2 位作者 LI Shao-wu YUAN Chun-guang ZHANG Hua-qing 《China Ocean Engineering》 SCIE EI CSCD 2024年第5期893-903,共11页
The typical cross-sectional form of a submerged floating tunnel plays a significant role in the dynamic response of the tunnel itself,which directly affects the overall design.In this work,a series of experiments invo... The typical cross-sectional form of a submerged floating tunnel plays a significant role in the dynamic response of the tunnel itself,which directly affects the overall design.In this work,a series of experiments involving wave action on a submerged floating tube cross section is reported to study its hydrodynamic load characteristics.Two typical cross section tube cylinders,circular and rectangular,are chosen.Experiments are carried out in a wave flume with waves of relatively low Keulegan-Carpenter(KC)numbers.Three relative depths of submergence of 0,0.25 and 0.5 are chosen.The measured wave forces in regular waves are used to analyze the horizontal force,vertical force and torque,and then the drag coefficient(Cd)and inertia coefficient(Cm)are derived.The results show that the drag coefficients at low KC numbers are large and decrease sharply with increasing KC number.The inertial coefficient Cm values in the vertical direction are about 70%larger than those in the horizontal direction.With an increase in aspect ratio(the ratio of the height to width of the structure),the ratio of inertia coefficient in the horizontal direction to that in the vertical direction increases remarkably.The inertia force coefficient is very sensitive to the submerged water depth and aspect ratio.The existing results may overestimate the actual force value. 展开更多
关键词 submerged floating tunnel tube cylinder wave force coefficient physical experiments
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SCHOOL DIFFICULTIES in Children Cancer Survivors: A Narrative Review and a Teacher Point-of-View
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作者 Fanny Delehaye Caroline Fayet Julien Lejeune 《Psycho-Oncologie》 SCIE 2024年第2期109-115,共7页
School difficulties are common in children cancer survivors and may be prognostic for the success of the patient social reintegration after the disease.Here,we carry out a narrative review of the literature from 2001 ... School difficulties are common in children cancer survivors and may be prognostic for the success of the patient social reintegration after the disease.Here,we carry out a narrative review of the literature from 2001 to 2022 to assess the school difficulties of these patients,the predictive factors of these difficulties,and the possible long-term consequences.We punctuate this review the practical point-of-view of a teacher dedicated to our hospital,who works with children with chronic diseases such as cancer.Therefore,we expose possible barriers and solutions to improve the scholar reintegration and limit the impact of cancer on the academic achievement. 展开更多
关键词 Cancer CHILDREN school
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Numerical Study on the Effect of Gap Diffraction on the Hydrodynamic Performance of A Floating Breakwater
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作者 BIAN Xiang-qian JI Chun-yan +2 位作者 XU Sheng GUO Jian-ting HUO Fa-li 《China Ocean Engineering》 SCIE EI CSCD 2024年第4期663-675,共13页
Two-dimensional(2D)flume experiments are useful in investigating the performances of floating breakwaters(FBs),including hydrodynamic performances,motion responses,and mooring forces.Designing a reasonable gap between... Two-dimensional(2D)flume experiments are useful in investigating the performances of floating breakwaters(FBs),including hydrodynamic performances,motion responses,and mooring forces.Designing a reasonable gap between the flume wall and the FBs is a critical step in 2D flume tests.However,research on the effect of the gap on the accuracy of 2D FB experimental results is scarce.To address this issue,a numerical wave tank is developed using CFD to estimate the wave-FB interaction of a moored dual-cylindrical FB,and the results are compared to experimental data from a previously published work.There is good agreement between them,indicating that the numerical model is sufficiently accurate.The numerical model is then applied to explore the effect of gap diffraction on the performance of FBs in2D experiments.It was discovered that the nondimensional gap length L_(Gap)/W_(Pool)should be smaller than 7.5%to ensure that the relative error of the transmission coefficient is smaller than 3%.The influence of the gap is also related to the entering wave properties,such as the wave height and period. 展开更多
关键词 floating breakwater diffraction effect GAP hydrodynamic performance model experiments CFD numerical simulation
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Relative peripheral refraction in school children with different refractive errors using a novel multispectral refraction topographer
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作者 Hui-Ling Hu Serena Zhe-Chuang Li +3 位作者 Ai-Ying Feng Hao-Xi Zhong Jing-Feng Mu Mei-Zhou Liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第8期1477-1482,共6页
AIM:To compare relative peripheral refraction(RPR)in Chinese school children with different refractive errors using multispectral refraction topography(MRT).METHODS:A total of 713 eyes of primary school children[172 e... AIM:To compare relative peripheral refraction(RPR)in Chinese school children with different refractive errors using multispectral refraction topography(MRT).METHODS:A total of 713 eyes of primary school children[172 emmetropia(E),429 low myopia(LM),80 moderate myopia(MM),and 32 low hypermetropia(LH)]aged 10 to 13y were analyzed.RPRs were measured using MRT without mydriasis.MRT results showed RPR at 0-15°(RPR 0-15),15°-30°(RPR 15-30),and 30°-45°(RPR 30-45)annular in the inferior(RPR-I),superior(RPR-S),nasal(RPR-N),and temporal(RPR-T)quadrants.Spherical equivalent(SE)was detected and calculated using an autorefractor.RESULTS:There were significant differences of RPR 15-30 between groups MM[0.02(-0.12;0.18)]and LH[-0.13(-0.36;0.12)](P<0.05),MM and E[-0.06(-0.20;0.10)](P<0.05),and LM[-0.02(-0.15;0.15)]and E(P<0.05).There were also significant differences of RPR 30-45 between groups MM[0.45(0.18;0.74)]and E[0.29(-0.09;0.67)](P<0.05),and LM[0.44(0.14;0.76)]and E(P<0.001).RPR values increased from the hyperopic to medium myopic group in each annular.There were significant differences of RPR-S between groups MM[-0.02(-0.60;0.30)]and E[-0.44(-0.89;-0.04)](P<0.001),and LM[-0.28(-0.71;0.12)]and E(P<0.05).There were also significant differences of RPR-T between groups MM[0.37(0.21;0.78)]and LH[0.14(-0.52;0.50)](P<0.05),LM[0.41(0.06;0.84)]and LH(P<0.05),and LM and E[0.29(-0.10;0.68),P<0.05].A Spearman’s correlation analysis showed a negative correlation between RPR and SE in the 15°-30°(P=0.005),30°-45°(P<0.05)annular(P=0.002),superior(P<0.001),and temporal(P=0.001)quadrants.CONCLUSION:Without pupil dilation,values for RPR 15-30,30-45,RPR-S,and T shows significant differences between myopic eyes and emmetropia,and the differences are negatively correlated with SE. 展开更多
关键词 relative peripheral refraction MYOPIA school children multispectral refraction topography
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Scattering of Water Waves by Dual Symmetric Inclined Floating Porous Barriers Using the DBEM
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作者 WANG Li-xian DENG Yan-wen +1 位作者 YE Yang-sha DENG Zheng-zhi 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期156-168,共13页
The scattering of normally incident water waves by two surface-piercing inclined perforated barriers in water with a uniform finite depth is investigated within the framework of linear water wave theory.Considering th... The scattering of normally incident water waves by two surface-piercing inclined perforated barriers in water with a uniform finite depth is investigated within the framework of linear water wave theory.Considering that thin barriers are zero-thickness,a novel numerical method involving the the coupling of the dual boundary element method(DBEM)with damping layers is applied.In order to effectively damp out the reflected waves,two damping layers,instead of pseudoboundaries are implemented near the two side boundaries of the computational domain.Thus,the modified linearized free surface boundary conditions are formulated and used for solving both the ordinary boundary integral equation as well as the hypersingular boundary integral equation for degenerate boundaries.The newly developed numerical method is validated against analytical methods using the matched eigenfunction expansion method for the special case of two vertical barriers or the inclined angle to the vertical being zero.The influence of the length of the two damping layers has been discussed.Moreover,these findings are also validated against previous results for several cases.After validation,the numerical results for the reflection coefficient,transmission coefficient and dissipation coefficient are obtained by varying the inclination angle and porosity-effect parameter.The effects of both the inclination angle and the porosity on the amplitudes of wave forces acting on both the front and rear barriers are also investigated.It is found that the effect of the inclination angle mainly shifts the location of the extremal values of the reflection and the transmission coefficients.Additionally,a moderate value of the porosity-parameter is quite effective at dissipating wave energy and mitigating the wave loads on dual barriers. 展开更多
关键词 dual boundary element method inclined perforated floating breakwater reflection coefficient transmission coefficient damping layer
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Comparisons of Wave Force Model Effects on the Structural Responses and Fatigue Loads of a Semi-Submersible Floating Wind Turbine
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作者 HAN Yanqing LE Conghuan +1 位作者 ZHANG Puyang XU Shengnan 《Journal of Ocean University of China》 CAS CSCD 2024年第1期69-79,共11页
The selection of wave force models will significantly impact the structural responses of floating wind turbines.In this study,comparisons of wave force model effects on the structural responses and fatigue loads of a ... The selection of wave force models will significantly impact the structural responses of floating wind turbines.In this study,comparisons of wave force model effects on the structural responses and fatigue loads of a semi-submersible floating wind turbine(SFWT)were conducted.Simulations were performed by employing the Morison equation(ME)with linear or second-order wave kinematics and potential flow theory(PFT)with first-or second-order wave forces.A comparison of regular waves,irregular waves,and coupled wind/waves analyses with the experimental data showed that many of the simulation results and experimental data are relatively consistent.However,notable discrepancies are found in the response amplitude operators for platform heave,tower base bending moment,and tension in mooring lines.PFT models give more satisfactory results of heave but more significant discrepan-cies in tower base bending moment than the ME models.In irregular wave analyses,low-frequency resonances were captured by PFT models with second-order difference-frequency terms,and high-frequency resonances were captured by the ME models or PFT models with second-order sum-frequency terms.These force models capture the response frequencies but do not reasonably predict the response amplitudes.The coupled wind/waves analyses showed more satisfactory results than the wave-only analyses.However,an important detail to note is that this satisfactory result is based on the overprediction of wind-induced responses. 展开更多
关键词 floating wind turbine wave force model potential flow theory Morison equation second-order wave forces
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Dynamic Analysis of a 10 MW Floating Offshore Wind Turbine Considering the Tower and Platform Flexibility
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作者 GAO Shan ZHANG Lixian +3 位作者 SHI Wei WANG Wenhua WANG Bin LI Xin 《Journal of Ocean University of China》 CAS CSCD 2024年第2期358-370,共13页
Recently,semisubmersible floating offshore wind turbine technologies have received considerable attention.For the coupled simulation of semisubmersible floating offshore wind energy,the platform is usually considered ... Recently,semisubmersible floating offshore wind turbine technologies have received considerable attention.For the coupled simulation of semisubmersible floating offshore wind energy,the platform is usually considered a rigid model,which could affect the calculation accuracy of the dynamic responses.The dynamic responses of a TripleSpar floating offshore wind turbine equipped with a 10 MW offshore wind turbine are discussed herein.The simulation of a floating offshore wind turbine under regular waves,white noise waves,and combined wind-wave conditions is conducted.The effects of the tower and platform flexibility on the motion and force responses of the TripleSpar semisubmersible floating offshore wind turbine are investigated.The results show that the flexibility of the tower and platform can influence the dynamic responses of a TripleSpar semisubmersible floating offshore wind turbine.Considering the flexibility of the tower and platform,the tower and platform pitch motions markedly increased compared with the fully rigid model.Moreover,the force responses,particularly for tower base loads,are considerably influenced by the flexibility of the tower and platform.Thus,the flexibility of the tower and platform for the coupled simulation of floating offshore wind turbines must be appropriately examined. 展开更多
关键词 floating offshore wind turbine TripleSpar semisubmersible platform rigidity and flexibility platform coupled simulation
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Commuting Space of Primary and Secondary Schools in the Context of Child Friendly Cities:A Case Study of Bajiao Street of Shijingshan District
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作者 LIU Ping PENG Li +2 位作者 WANG Zhihao CONG Jing DING Yuqi 《Journal of Landscape Research》 2024年第1期22-26,30,共6页
With the continuous promotion of the construction of child friendly cities,the school commuting space is an important component of the construction of child friendly roads.Based on the background of child friendly cit... With the continuous promotion of the construction of child friendly cities,the school commuting space is an important component of the construction of child friendly roads.Based on the background of child friendly cities,the commuting space of 11 primary and secondary schools in Bajiao Street is analyzed through literature analysis and field research methods.Firstly,the relevant literature on school commuting space is sorted out,and the characteristics of school commuting space are summarized,including transportation,landscape,culture,leisure,and security.Secondly,the characteristics of commuting space of primary and secondary schools in Bajiao Street are analyzed from three aspects:in front of the school gate,path space,and node space.This paper aims to provide reference and guidance for the future construction of children’s walking school commuting and promote the construction of a child friendly city. 展开更多
关键词 Child friendly cities school commuting space Bajiao Street Primary and secondary schools
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Design of Ocean Floating Structures:Prediction of Hydrodynamic Coefficients
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作者 LI Wei FAN Shaotao +1 位作者 WANG Jinxi LIU Tianhui 《南方能源建设》 2024年第6期18-32,共15页
[Introduction] Accurate calculation of the hydrodynamic coefficients for floating structures and the investigation of the flow field distribution around floating bodies on the marine free surface are essential for imp... [Introduction] Accurate calculation of the hydrodynamic coefficients for floating structures and the investigation of the flow field distribution around floating bodies on the marine free surface are essential for improving the engineering design and application of marine structures.[Method] This study utilized the computational fluid dynamics(CFD) approach and the Reynolds Averaged NavierStokes(RANS) method and considered the effects of viscosity and free surface interactions on the hydrodynamic behavior of floating structures.By employing the dynamic mesh technique,this study simulated the periodic movements of simplified three-dimensional(3D)shapes:spheres,cylinders,and cubes,which were representative of complex marine structures.The volume of fluid(VOF) method was leveraged to accurately track the nonlinear behavior of the free surface.In this analysis,the added mass and damping coefficients for the fundamental modes of motion(surge,heave,and roll) were calculated across a spectrum of frequencies,facilitating the fast determination of hydrodynamic forces and moments exerted on floating structures.[Result] The results of this study are not only consistent with the results of the 3D potential flow theory but also further reflect the role of viscosity.This method can be used for precise calculation of the hydrodynamic coefficients of floating structures and for describing the flow field of such structures in motion on a free surface.[Conclusion] The methodology presented goes beyond the traditional potential flow approach. 展开更多
关键词 Computational fluid dynamics ocean floating structures hydrodynamic coefficients fluid-structure interaction
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Research on Cultural Consumption and Urban Integration of Floating Population
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作者 Zhang Rui Dai Xiaowen 《Contemporary Social Sciences》 2024年第2期16-33,共18页
This paper examined the relationship between cultural consumption and the floating population’s integration into host cities based on data from China’s Seventh National Population Census and the 2018 China Migrants ... This paper examined the relationship between cultural consumption and the floating population’s integration into host cities based on data from China’s Seventh National Population Census and the 2018 China Migrants Dynamic Survey(CMDS).The findings indicate that improving the floating population’s consumption level and quality,especially the quality of development-oriented cultural consumption,can significantly improve the level of their integration.Moreover,development-oriented cultural consumption has a positive effect on the floating population’s integration and social participation,while entertainment-oriented cultural consumption facilitates their integration mainly by improving their sense of well-being.These findings could guide policymakers in developing targeted cultural consumption policies,implementing specific regional industry adjustments,and expanding domestic consumption demand. 展开更多
关键词 cultural consumption floating population urban integration social participation sense of well-being
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