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韩国补课如何影响数学成绩?——基于TIMSS 2019数据的双层线性模型分析

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复旦教育论坛 2024年第3期22卷 68-81页

作者：冷帝豪波士顿学院林奇教育与人类发展学院波士顿02467

韩国中小学生普遍补课,背后的关键假设是补课有利于提高学习成绩,但是补课和成绩的关系究竟如何,目前尚无定论。此外,补课的作用可能因条件而异,有必要更加细致地考察补课对不同群体的作用。本研究基于“国际大型数学与科学趋势研究”(T... 详细信息

韩国中小学生普遍补课,背后的关键假设是补课有利于提高学习成绩,但是补课和成绩的关系究竟如何,目前尚无定论。此外,补课的作用可能因条件而异,有必要更加细致地考察补课对不同群体的作用。本研究基于“国际大型数学与科学趋势研究”(TIMSS)2019八年级测评数据,采用双层次线性模型进行分析,发现韩国八年级学生补课时间越长,数学成绩就越好。在此基础上,如果学生所在学校平均补课时间长,学生成绩将额外增加;这种作用可被该校学生的整体家境组成所部分解释。学生补课时长与成绩的关系既不因学校而异,也不因其学业水平的高低而异;但是学生家庭经济与文化资本越薄弱,补课久与成绩提升的关系越大。本研究还发现,校内数学教师的教学水平能够在一定程度上中和补课与成绩的关系,但是这种作用比较有限。韩国已然形成补课主导的教育生态,补课对成绩有顽强的预测力,其背后反映的是学生与家长在学业竞争中胜出的需求无法在公办教育中得到满足;反过来,韩国的补课市场提供了更加多元化、个性化的教育。

关键词：补课影子教育 TIMSS 多层线性模型数学成绩

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考虑差异化需求的电动汽车充电调度策略

控制与决策 2024年第3期39卷 795-803页

作者：蔡凌郭戈施冷安东东北大学秦皇岛分校控制工程学院河北秦皇岛066004

电动汽车行驶里程短、充电时间长是影响驾驶体验的关键.通过对电网、充电设备进行大规模升级的方法减少充电时间,成本昂贵,因此充分利用现有路网、电网资源,制定智能充电调度策略成为提高驾驶体验的重要手段.考虑到驾驶者对充电时间敏... 详细信息

电动汽车行驶里程短、充电时间长是影响驾驶体验的关键.通过对电网、充电设备进行大规模升级的方法减少充电时间,成本昂贵,因此充分利用现有路网、电网资源,制定智能充电调度策略成为提高驾驶体验的重要手段.考虑到驾驶者对充电时间敏感度的异质性,提出具有差异化的调度策略以满足不同优先级驾驶者的需求.首先,为均衡不同优先级驾驶者的利益,提出一种基于动态截断机制的两优先级队列模型;其次,定义充电站的准入原则,保证高优先级驾驶者对预留桩的使用权及对空闲桩的优先抢占权;然后,提出基于截断机制的双层优化模型CCPQ(charging with cut-off priority queue),在顶层高优先级车辆与充电桩最优匹配的基础上,设计底层低优先级车辆的分配策略优化模型,将最小化低优先级驾驶者的总等待时间构建为凸优化问题;最后,通过仿真验证策略的有效性及优越性.

关键词：电动汽车充电策略区分服务预约截断优先级队列凸优化

High power cladding-pumped low quantum defect Raman fiber amplifier

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Photonics Research 2024年第5期12卷 995-1003页

作者： YANG ZHANG JIANGMING Xu JUNRUI LIANG SICHENG LI JUN YE XIAOYA MA TIANFU YAO ZHIYONG PAN JINYONG leng PU ZHOU College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China Nanhu Laser Laboratory National University of Defense TechnologyChangsha 410073China Hunan Provincial Key Laboratory of High Energy Laser Technology National University of Defense TechnologyChangsha 410073China

Heat generated by the quantum defect(QD)in optically pumped lasers can result in detrimental effects such as mode instability,frequency noise,and even catastrophic ***,we demonstrated that boson-peakbased Raman fiber lasers have great potential in low QD laser *** their power scalability and heat load characteristics have yet to be ***,we demonstrate a boson-peak-based Raman fiber amplifier(RFA)with 815 W output power and a QD of 1.3%.The low heat generation characteristics of this low QD RFA are *** experimental and simulation results show that at this power level,the heat load of the low QD RFA is significantly lower than that of the conventional RFA with a QD of 4.8%.Thanks to its low heat generation characteristics,the proposed phosphosilicate-fiber-based low QD RFA provides an effective solution for the intractable thermal issue in optically pumped lasers,which is of significance in reducing the laser’s noise,improving the laser’s stability and safety,and solving the challenge of heat removing.

关键词： pumped fiber amplifier

Near-field radiative heat transfer between nanoporous GaN films

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Chinese Physics B 2024年第4期33卷 109-120页

作者：韩晓政张纪红刘皓佗吴小虎冷惠文 School of Electromechanical and Automotive Engineering Yantai UniversityYantai 264005China Key Laboratory of Advanced Manufacturing and Intelligent Technology Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China Thermal Science Research Center Shandong Institute of Advanced TechnologyJinan 250100China

Photon tunneling effects give rise to surface waves,amplifying radiative heat transfer in the near-field *** research has highlighted that the introduction of nanopores into materials creates additional pathways for heat transfer,leading to a substantial enhancement of near-field radiative heat transfer(NFRHT).Being a direct bandgap semiconductor,GaN has high thermal conductivity and stable resistance at high temperatures,and holds significant potential for applications in optoelectronic ***,study of NFRHT between nanoporous GaN films is currently lacking,hence the physical mechanism for adding nanopores to GaN films remains to be discussed in the field of *** this work,we delve into the NFRHT of GaN nanoporous films in terms of gap distance,GaN film thickness and the vacuum filling *** results demonstrate a 27.2%increase in heat flux for a 10 nm gap when the nanoporous filling ratio is ***,the spectral heat flux exhibits redshift with increase in the vacuum filling *** be more precise,the peak of spectral heat flux moves fromω=1.31×10^(14)rad·s^(-1)toω=1.23×10^(14)rad·s^(-1)when the vacuum filling ratio changes from f=0.1 to f=0.5;this can be attributed to the excitation of surface phonon *** introduction of graphene into these configurations can highly enhance the NFRHT,and the spectral heat flux exhibits a blueshift with increase in the vacuum filling ratio,which can be explained by the excitation of surface plasmon *** findings offer theoretical insights that can guide the extensive utilization of porous structures in thermal control,management and thermal modulation.

关键词： near-field radiative heat transfer nanoporous GaN film surface phonon polaritons surface plasmon polaritons

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2023年夏季我国气候异常特征及成因分析

气象 2024年第1期50卷 115-125页

作者：支蓉高辉孙冷国家气候中心中国气象局气候研究开放实验室北京100081

2023年夏季,我国气候特征整体表现为“温高雨少”,区域性、阶段性高温、旱涝等气象灾害明显。降水的空间分布差异显著,主要多雨区位于我国北方,松花江、海河流域出现严重汛情。生成和登陆台风频数均较常年同期偏少,但北上台风却对京津... 详细信息

2023年夏季,我国气候特征整体表现为“温高雨少”,区域性、阶段性高温、旱涝等气象灾害明显。降水的空间分布差异显著,主要多雨区位于我国北方,松花江、海河流域出现严重汛情。生成和登陆台风频数均较常年同期偏少,但北上台风却对京津冀等地造成极其严重的雨涝灾害。2023年夏季我国气温为1961年以来历史次高,北方地区暖异常明显,华北、西北等地区阶段性高温热浪尤为突出。华北、东北地区降水偏多是由不同环流系统造成的。其中,华北南部降水异常偏多主要由7月底至8月初一次极为罕见的天气尺度持续性极端降水过程所致,台风杜苏芮和卡努外围环流与异常偏西、偏北的西太平洋副热带高压相配合,再加上太行山东麓的地形效应是其主要原因。盛夏东北东部异常偏南风引导的水汽输送在整个对流层都异常偏强,造成东北北部和东部降水明显偏多,这一异常环流与初夏巴伦支海海冰密集度减小及盛夏西北太平洋海温异常偏暖均有一定关联。

关键词：夏季降水高温热浪巴伦支海海冰密集度台风杜苏芮台风卡努

Analysis of Epidemiological Characteristics of Varicella Before and After the Implementation of the Two-dose Varicella Vaccine Immunization Program in Banan District of Chongqing City

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Journal of Clinical and Nursing Research 2024年第6期8卷 335-344页

作者： Yundan Cheng Ju Yan Xiaoling Zhu Xiaoxia Jiang Jingzhi Li Hao leng Chongqing Banan District Disease Prevention and Control Center 79 Bay County AvenueYudong StreetBanan DistrictChongqing 401320China

Objective:To explore the changes in the epidemiological characteristics of varicella before and after implementing the two-dose varicella vaccine(VarV)immunization program in the Banan District of Chongqing and to provide a reference for future epidemic prevention and ***:The data of reported varicella cases in Banan District from 2014 to 2023 were collected and analyzed using the China Disease Prevention and Control Information *** epidemiological methods were employed to assess the changes in the reported incidence of varicella before(2014-2018)and after(2019-2023)the implementation of the two-dose VarV immunization ***:The average annual reported incidence rate of varicella in Banan District from 2014 to 2023 was 81.53 per 100,*** 2014 to 2018,the reported incidence rate showed an upward trend year by year(trend x2=223.96,P<0.05).However,the reported incidence rate decreased from 2019 to 2023(trend x?=189.51,P<0.05).Before and after the adjustment of the immunization program,the reported incidence rate for the 5-9 years old group was 774.62 per 100,000 and 476.98 per 100,000,respectively,with a statistically significant difference(x2=161.26,P<0.05).The onset of varicella showed a bimodal distribution,with peak incidence periods in May-June and *** 2014 to 2023,a total of 155,181 doses of VarV were administered in Banan *** estimated annual vaccination rate for the first varicella vaccine(VarV1)from 2019 to 2023 was 86.28%,and for the second dose(VarV2)was 59.18%.The primary vaccination targets were the 5-9-year-old group,accounting for 64.21%.Conclusion:After implementing the two-dose VarV immunization program in Banan District,the vaccination rate increased yearly,and the reported incidence of varicella showed a downward *** incidence rate of varicella in children aged 5-9 years reduced significantly,but the overall downward trend for the entire population was not as ***

关键词： Varicella Varicella vaccine Immunization program Epidemiological characteristics

2023年汛期气候预测效果评述及先兆信号分析

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气象 2024年第3期50卷 377-386页

作者：支蓉高辉孙冷国家气候中心中国气象局气候研究开放实验室北京100081

2023年夏季,我国整体表现为高温少雨的特征,旱涝分布不均。夏季台风虽然生成和登陆个数均较常年偏少,但破坏力极强。华北、西北等地阶段性高温事件异常突出,但长江流域的高温干旱强度明显弱于2022年同期。从预测效果来看,2023年汛期预... 详细信息

2023年夏季,我国整体表现为高温少雨的特征,旱涝分布不均。夏季台风虽然生成和登陆个数均较常年偏少,但破坏力极强。华北、西北等地阶段性高温事件异常突出,但长江流域的高温干旱强度明显弱于2022年同期。从预测效果来看,2023年汛期预测较好把握了我国北方主雨带特征,对松花江流域、嫩江流域、海河流域可能出现的较重汛情做出了准确的预测预警。对夏季热带气旋的生成个数、主要路径、影响区域等的预测与实况较为相符。对夏季全国大部地区气温偏高的特征预测与实况一致,并明确指出,长江流域发生类似2022年夏季大范围持续性高温干旱事件的可能性低。汛期预测的不足之处主要在于对华南等地的降水预测与实况出现较大偏差,对华北、黄淮等地的高温过程极端性估计不足。针对2023年汛期降水的先兆信号及其预报性能进行了回顾和评估,无论是年代际尺度还是年际尺度外强迫信号,均对我国北方主雨带有较好的指示意义。同时,几乎所有先兆信号都对华南降水给出了一致的错误信息,是导致华南降水预报失败的主要原因。

关键词：夏季降水高温热浪热带气旋先兆信号

“民歌调解”的适用机理与困境破解认同研究——基于贵州省黔东南州榕江县“民歌法庭”的考察

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贵州民族研究 2024年第1期45卷 53-60页

作者：冷传莉陈桐贵州大学法学院贵州贵阳550025

民歌与调解的“联姻”方式是榕江县法院结合本地区民族特色所形成的纠纷化解方式之一。“民歌调解”在当地得以有效适用的主要原因有两个方面:一是民歌承载当地共同遵循的社会规范,并将其予以通俗化与柔性化;二是受众仍受“息讼”传统... 详细信息

民歌与调解的“联姻”方式是榕江县法院结合本地区民族特色所形成的纠纷化解方式之一。“民歌调解”在当地得以有效适用的主要原因有两个方面:一是民歌承载当地共同遵循的社会规范,并将其予以通俗化与柔性化;二是受众仍受“息讼”传统的影响且集体主义观浓厚。“民歌调解”亦存在适用困境,主要表现为规范供给不足、重视秩序维护的调解倾向以及专门的调解人才难以为继等。为有效推进民族地区法治建设及做好民族工作,应立足于民族地区特有丰富的本土情法资源,完善相关实体与程序规范,坚持以人为本,明确调解的价值中立定位,补充并强化人才可持续补给机制,借此推动多元共治下少数民族基层治理模式日趋完善。

关键词：民族地区特色纠纷化解方式 “民歌调解” 本土资源基层治理

A Case of Investigation and Diagnosis of Immune Thrombocytopenic Purpura After Vaccination of COVID-19 Inactivated Vaccine

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Journal of Clinical and Nursing Research 2024年第6期8卷 328-334页

作者： Hao leng Ju Yan Xiaoling Zhu Xiaoxia Jiang Jingzhi Li Yundan Cheng Communicable Disease Prevention and Control and Immunization Program Chongqing Banan District Disease Prevention and Control CenterChongqing 401320China

Objective:Analyze the relationship between inoculating one case of the COVID-19 inactivated vaccine(Vero cell)and immune thrombocytopenic purpura to provide a reference for the standardized handling of adverse events following ***:According to the"National Monitoring Program for Suspected Adverse Reactions to Vaccinations,"an on-site investigation,data collection and analysis,expert group diagnosis,and medical association assessment were conducted on a case of immune thrombocytopenic purpura in District A of Chongqing after vaccination with the inactivated COVID-19 *** assessment report was delivered to the three relevant parties,the case was reviewed,and the experience was ***:The investigation and diagnosis by the district-level vaccination abnormal reaction expert group concluded that the disease that occurred after vaccination with the COVID-19 inactivated vaccine was secondary immune thrombocytopenic purpura,an abnormal reaction to the *** medical damage was classified as Level II Grade *** vaccine production enterprise raised objections to this *** re-assessment by the municipal-level medical association,the conclusion was consistent with that of the district-level medical *** vaccine production enterprise did not raise any further ***:Through active collaboration among district and municipal-level medical associations,disease control institutions,and vaccination units,the recipients have been promptly and effectively treated,providing financial support for their subsequent treatment and safeguarding their *** investigation and disposal procedures for adverse events following immunization in Chongqing are clear,and the mechanism is *** is necessary to continue strengthening the monitoring of adverse events following immunization according to the existing plan and to ensure timely and standardized ***,it is crucial to strengthen vacci

关键词： Adverse events following immunization Immunizations COVID-19 inactivated vaccine(Vero cell) Immune thrombocytopenic purpura Investigation and diagnosis