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技术重塑治理关系与数字治理“内卷化”——以“12345”热线驱动市域治理为例 被引量:1
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作者 陈锋 王泽林 《探索》 北大核心 2024年第1期115-128,共14页
目前,推动来自数据资源的技术驱动与政府行政体系融合,已成为推进国家治理体系和治理能力现代化的应有之义。数字治理对民众和政府具有双向赋能意义,但需要有效协同数字技术与科层体制之间的关系、平衡多元治理主体之间的关系,避免陷入... 目前,推动来自数据资源的技术驱动与政府行政体系融合,已成为推进国家治理体系和治理能力现代化的应有之义。数字治理对民众和政府具有双向赋能意义,但需要有效协同数字技术与科层体制之间的关系、平衡多元治理主体之间的关系,避免陷入数字治理“内卷化”的困境。以A市“12345”热线驱动市域治理为例,数字治理的“内卷化”生发于数字信息在行政体制内运行的不同阶段。在诉求信息输入阶段,信息传播的跨时空性使群众从逐级传递变为直接面对上级政府,上级政府实现对诉求处理全流程的监督和考核,形塑了去中间化治理主体关系,导致治理内容、数量和成本不断增长,同时基层政府自主治理的空间减少。在诉求信息筛选阶段,现实诉求以简化和标准化的信息形式在热线数字系统中闭环流转,治理实践中诉求解决的情境关系出现脱域。原先可以在治理情境中被识别的不合理诉求和反复提交的诉求,伪装成单一诉求从而突破原有治理结构的抑制,挤占了大量的治理注意力和治理资源,破坏原有的治理传统与治理规则,造成“无理”诉求工单在热线系统中的空转。在诉求信息处理或执行阶段,受到科层压力与信息传递的乘数效应影响,诉求治理的责任关系发生改变,基层组织由于压力过载产生目标替代行为。数字治理“内卷化”是数字技术逻辑对治理逻辑与治理关系的改造,使数字技术从辅助治理的工具手段转变为主导基层工作的关键变量。数字技术对治理的反噬后果,不仅表现为治理效能的低效增长,还体现在工具理性思维对人本思维的侵蚀与替代。破解数字治理的“内卷化”问题,需要审视数字技术引发的治理关系变革,发挥数字信息在治理体系与治理能力现代化中的支撑作用,在市域层面重点发挥数据挖掘的决策辅助功能,厘清各个治理主体关系责权利边界,避免数字化的过度监督。数字治理要辅助场景式治理,重点激发基层组织和群众的主体性。 展开更多
关键词 数字治理 市域治理 内卷化 “12345”热线
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高职大思政课“12345”实践育人模式的构建与实施——以西安航空职业技术学院为例
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作者 闫红茹 《新疆职业教育研究》 2024年第2期27-30,共4页
在世界百年未有之大变局和中华民族伟大复兴战略全局时代背景下,思政课教学要与社会大课堂结合起来,充分挖掘鲜活的育人素材,培养担当民族复兴重任的时代新人。本文以西安航空职业技术学院发挥航空文化资源优势、开展大思政课实践教学... 在世界百年未有之大变局和中华民族伟大复兴战略全局时代背景下,思政课教学要与社会大课堂结合起来,充分挖掘鲜活的育人素材,培养担当民族复兴重任的时代新人。本文以西安航空职业技术学院发挥航空文化资源优势、开展大思政课实践教学、构建“12345”实践育人模式为例,为解决高职思政课教学中存在的专职教学团队与特聘教授之间沟通不畅、理论教学与实践教学相脱节、课程资源开发与利用不充分、教学形式单一等问题提供思路。 展开更多
关键词 高职 思政课 大思政课 “12345”实践育人模式
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基于“12345”热线转办的投诉分析及措施探讨
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作者 顾海燕 《中国卫生标准管理》 2024年第5期45-48,共4页
目的归纳总结“12345”热线转办投诉的情况,分析原因,提出处理措施。方法选取2020年1月—2022年12月“12345”热线转办的启东市中医院投诉763件进行分析,分析投诉类型,总结发生投诉的科室分布情况,同时总结引起投诉的相关原因,提出处理... 目的归纳总结“12345”热线转办投诉的情况,分析原因,提出处理措施。方法选取2020年1月—2022年12月“12345”热线转办的启东市中医院投诉763件进行分析,分析投诉类型,总结发生投诉的科室分布情况,同时总结引起投诉的相关原因,提出处理措施。结果763件投诉情况中,涉及院感防控方面的总计380件,占比49.80%,其他涉及医院诊疗服务、就医流程、医疗收费等情况。涉及投诉的科室包括门诊医技科室、病区、总务、药房、收费等。分析结果显示,院感防控是3年内引起投诉的主要原因;其次是医患沟通不到位、医疗质量问题、服务态度问题、收费不合理等。结合原因提出相应处理对策。结论通过“12345”热线能够一定程度使医院了解投诉信息,拓宽投诉通道,改进服务机制,提升服务质量,以建立和谐、融洽的医患关系。 展开更多
关键词 “12345”热线 转办 投诉 措施 院感防控 服务态度
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12345平台的法律地位——数字法治政府的组织法观察 被引量:2
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作者 王敬波 董媛媛 《新疆师范大学学报(哲学社会科学版)》 北大核心 2024年第3期25-35,共11页
12345平台内生出一种不同于行政权力、社会权力的新型权力——数字权力,其产生的主要原因是国家治理需要,基础是合作行政,载体是数字技术。12345平台数字权力的扩张带来行政组织法难题,包括数字权力改变传统权力结构,挑战组织法的职权... 12345平台内生出一种不同于行政权力、社会权力的新型权力——数字权力,其产生的主要原因是国家治理需要,基础是合作行政,载体是数字技术。12345平台数字权力的扩张带来行政组织法难题,包括数字权力改变传统权力结构,挑战组织法的职权法定原则;数字权力模糊传统权力边界,带来行政合法性难题;数字权力带来去中心化,引发主体归责机制模糊化。12345平台是一种新的行政组织运作模式,“新”表现为一种以行政任务为导向的整体运作模式,形成一个动态化的数字生态系统;是以新公共管理为基础、逐渐转向网络治理范式的新型合作模式。12345平台作为数字政府建设的产物,应受行政组织法调整。在数字法治政府建设背景下,应以整体政府改革为面向,科学调整行政组织法体系;以数字素养、监督机制、技术和法律手段解决行政合法性难题;从采购思维转向规则制定思维,依法设计负责任的人工智能。 展开更多
关键词 12345平台 法律地位 数字权力 数字法治政府 组织法
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基于主客观环流分型的强降水数值预报MODE检验方法及其在2019年暖季东北地区的应用
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作者 齐铎 崔晓鹏 +4 位作者 陈力强 黄丽君 刘松涛 卜文惠 王承伟 《大气科学》 CSCD 北大核心 2024年第3期1113-1130,共18页
本文构建了基于主客观环流分型的强降水数值预报空间检验(MODE)方法框架,并利用该框架对欧洲中期天气预报中心全球模式(ECMWF)和中国气象局区域中尺度数值天气预报模式(CMA_MESO)的2019年暖季东北地区强降水预报进行检验。结果表明,201... 本文构建了基于主客观环流分型的强降水数值预报空间检验(MODE)方法框架,并利用该框架对欧洲中期天气预报中心全球模式(ECMWF)和中国气象局区域中尺度数值天气预报模式(CMA_MESO)的2019年暖季东北地区强降水预报进行检验。结果表明,2019年暖季东北地区54个强降水日的环流型可分为:西风槽型(15个)、副热带高压影响型(13个)、急流型(5个)、西部(12个)和东部冷涡型(9个)。其中,西风槽型和急流型以区域性强降水为主,模式对其强降水发生与否的预报能力强,TS评分较高;西部、东部冷涡型强降水的局地性强,模式对其强降水发生与否的预报能力差,TS评分低;副热带高压影响型也以区域性强降水为主,模式对其强降水发生与否的预报能力也比较强,但是对其强降水质心位置、强度、面积等属性预报偏差较大,TS评分也相对较低。另外,从两种模式预报性能对比看,CMA_MESO强降水强度和面积预报较实况普遍偏强,虽然其预报的TS评分一般高于ECMWF,但其对强降水预报的空报率也都比ECMWF大,对强降水的属性预报偏差一致性一般也低于ECMWF,其预报的可订正性整体上不及ECMWF。 展开更多
关键词 主客观融合环流分型 东北冷涡客观识别 强降水 数值预报 mode检验
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“12345”热线诊疗投诉特征、产生原因及改进建议分析——以江苏省某口腔医院为例
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作者 马震 杨毅 王磊 《南京中医药大学学报(社会科学版)》 2024年第3期191-197,共7页
正视口腔患者的合理诉求,及时、有效地处理患者的诊疗投诉,关系到口腔医疗服务质量提升与患者就医体验改善,具有重要意义。通过对江苏省某三甲口腔专科医院2019-2022年“12345”热线受理的1 778例诊疗投诉进行分析发现,诊疗投诉数和每... 正视口腔患者的合理诉求,及时、有效地处理患者的诊疗投诉,关系到口腔医疗服务质量提升与患者就医体验改善,具有重要意义。通过对江苏省某三甲口腔专科医院2019-2022年“12345”热线受理的1 778例诊疗投诉进行分析发现,诊疗投诉数和每万人次诊疗投诉数均逐年上升,单月诊疗投诉数受到疫情防控政策影响呈现波动趋势,患者投诉内容主要集中在工作流程、疫情防控、医疗质量、停诊问题等方面。导致上述问题的原因主要包括突发公共卫生事件的影响、医疗资源配置不合理、医务人员医疗技术不足与职业倦怠、医患双方的认知存在差异、投诉处理机制与医疗纠纷管理不适配。为此,建议提升突发公共卫生事件的处置能力;合理配置医疗资源,持续优化诊疗流程;提升医疗服务水平,积极缓解职业倦怠;消除医患认知差异,推动共同决策模式构建;优化投诉管理机制,避免医患矛盾加剧。 展开更多
关键词 “12345”热线 诊疗投诉 口腔医院 医患关系 医疗质量 医疗资源
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一种基于粗糙熵的改进K-modes聚类算法
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作者 刘财辉 曾雄 谢德华 《南京理工大学学报》 CAS CSCD 北大核心 2024年第3期335-341,共7页
K-modes聚类算法被广泛应用于人工智能、数据挖掘等领域。传统的K-modes聚类算法有不错的聚类效果,但是存在迭代次数多、计算量大、容易受到冗余属性的干扰等问题,且仅采用简单的0-1匹配的方法来定义2个样本属性值之间的距离,没有充分... K-modes聚类算法被广泛应用于人工智能、数据挖掘等领域。传统的K-modes聚类算法有不错的聚类效果,但是存在迭代次数多、计算量大、容易受到冗余属性的干扰等问题,且仅采用简单的0-1匹配的方法来定义2个样本属性值之间的距离,没有充分考虑每个属性对聚类结果的影响。针对上述问题,该文将粗糙熵引入K-modes算法。首先利用粗糙集属性约简算法消除冗余属性,确定各属性的重要程度;然后利用粗糙熵确定每个属性的权重,从而定义新的类内距离。将该文所提算法与传统的K-modes聚类算法分别在4组公开数据集上进行对比试验。试验结果表明,该文所提算法聚类准确率比传统的K-modes聚类算法更高。 展开更多
关键词 聚类 K-modes算法 粗糙集 粗糙熵 属性约简 权重
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以“12345”问题为导向提升患者满意度的研究
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作者 马翠业 王媛媛 《中国卫生标准管理》 2024年第3期48-53,共6页
目的以“12345”政务热线患者诉求相关数据为基础,分析公立医院投诉来源,寻求提升患者的满意度途径。方法对比连云港某公立医院2020年1月—2022年12月指标情况及变化趋势,运用统计学描述性统计方法完成相关数据的收集整理,利用鱼骨图、... 目的以“12345”政务热线患者诉求相关数据为基础,分析公立医院投诉来源,寻求提升患者的满意度途径。方法对比连云港某公立医院2020年1月—2022年12月指标情况及变化趋势,运用统计学描述性统计方法完成相关数据的收集整理,利用鱼骨图、头脑风暴法汇总分析。结果由于缺乏监督考核体系应用、机制不完善等原因导致患者满意度不高,通过成立监管机构、优化就医流程、加强医患沟通等措施,并加强内部问题的整改与落实,建立健全考核评价及服务监督体系;并将其纳入考核体系,强化监督问效,形成一套科学完善的考核评价和服务监督体系;“12345”热线类似工单逐年降低。结论通过本研究成果的实施,患者满意度逐年增长,就医满意度和获得感不断提升,值得在公立医院中进一步推广。 展开更多
关键词 公立医院 “12345”热线 问题导向 监督质效 考核评价体系 满意度
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Transition from a filamentary mode to a diffuse one with varying distance from needle to stream of an argon plasma jet
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作者 许慧敏 高敬格 +3 位作者 贾鹏英 冉俊霞 陈俊宇 李金懋 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期539-544,共6页
Plasma jet has extensive application potentials in various fields, which normally operates in a diffuse mode when helium is used as the working gas. However, when less expensive argon is used, the plasma jet often ope... Plasma jet has extensive application potentials in various fields, which normally operates in a diffuse mode when helium is used as the working gas. However, when less expensive argon is used, the plasma jet often operates in a filamentary mode. Compared to the filamentary mode, the diffuse mode is more desirable for applications. Hence, many efforts have been exerted to accomplish the diffuse mode of the argon plasma jet. In this paper, a novel single-needle argon plasma jet is developed to obtain the diffuse mode. It is found that the plasma jet operates in the filamentary mode when the distance from the needle tip to the central line of the argon stream(d) is short. It transits to the diffuse mode with increasing d. For the diffuse mode, there is always one discharge pulse per voltage cycle, which initiates at the rising edge of the positive voltage. For comparison, the number of discharge pulse increases with an increase in the peak voltage for the filamentary mode. Fast photography reveals that the plasma plume in the filamentary mode results from a guided positive streamer,which propagates in the argon stream. However, the plume in the diffuse mode originates from a branched streamer, which propagates in the interfacial layer between the argon stream and the surrounding air. By optical emission spectroscopy,plasma parameters are investigated for the two discharge modes, which show a similar trend with increasing d. The diffuse mode has lower electron temperature, electron density, vibrational temperature, and gas temperature compared to the filamentary mode. 展开更多
关键词 plasma jet diffuse mode filamentary mode optical emission spectroscopy
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MODE降水检验评价指标改进及卷积半径应用
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作者 杨富燕 陈百炼 +2 位作者 彭芳 胡欣欣 李彦霖 《气象科技》 2024年第2期218-227,共10页
基于对象的诊断检验方法(MODE)受降水临界值、卷积半径、属性权重等参数的影响,合理选取卷积半径并准确表征预报场与观测场之间的空间相似度决定了MODE的应用效果。本文基于2020年夏季贵州54个降水个例,以多源融合降水(CMPA)作为实况,使... 基于对象的诊断检验方法(MODE)受降水临界值、卷积半径、属性权重等参数的影响,合理选取卷积半径并准确表征预报场与观测场之间的空间相似度决定了MODE的应用效果。本文基于2020年夏季贵州54个降水个例,以多源融合降水(CMPA)作为实况,使用MODE和FSS评分(Fractions Skill Score)对中国气象局广东快速更新同化数值预报系统(CMA-GD)24 h日降水预报进行空间检验。结果表明:卷积半径过小易造成MODE提取降水对象过多,而卷积半径过大则导致局部降水信息丢失,无法从降水场中提取到降水对象。不同卷积半径下计算的最大相似度中值(M_(MI))存在突变。在M_(MI)基础上引入面积权重构造面积平均最大相似度(A_(MMI))。A_(MMI)不受提取降水对象个数的影响,较M_(MI)更具有稳定性,用于表征降水场之间的整体空间相似程度更为合理。根据对象总面积随卷积半径的变化将降水分为大范围降水和局部降水2类。大范围降水平均总面积随着卷积半径的增加而增加,A_(MMI)随卷积半径变化不大。随着卷积半径的增加,局部降水平均总面积减小,平均A_(MMI)有所减小。局部降水对卷积半径选取较为敏感,以观测场对象面积变化不超过10%的最大半径作为卷积半径有助于保留降水场大部分信息。 展开更多
关键词 降水 mode 空间检验 参数
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Suppression of the m/n=2/1 tearing mode by electron cyclotron resonance heating on J-TEXT
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作者 方建港 陈忠勇 +13 位作者 严伟 王能超 毛飞越 罗蔷 玄子健 陈曦璇 任正康 张峰 黄梅 夏冬辉 杨州军 陈志鹏 丁永华 the J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第8期8-17,共10页
Stabilization of tearing modes and neoclassical tearing modes is of great importance for tokamak operation.Electron cyclotron waves(ECWs)have been extensively used to stabilize the tearing modes with the virtue of hig... Stabilization of tearing modes and neoclassical tearing modes is of great importance for tokamak operation.Electron cyclotron waves(ECWs)have been extensively used to stabilize the tearing modes with the virtue of highly localized power deposition.Complete suppression of the m/n=2/1 tearing mode(TM)by electron cyclotron resonance heating(ECRH)has been achieved successfully on the J-TEXT tokamak.The effects of ECW deposition location and power amplitude on the 2/1 TM suppression have been investigated.It is found that the suppression is more effective when the ECW power is deposited closer to the rational surface.As the ECW power increases to approximately 230 k W,the 2/1 TM can be completely suppressed.The island rotation frequency is increased when the island width is reduced.The experimental results show that the local heating inside the magnetic island and the resulting temperature perturbation increase at the O-point of the island play dominant roles in TM suppression.As the ECW power increases,the 2/1 island is suppressed to smaller island width,and the flow shear also plays a stabilizing effect on small magnetic islands.With the stabilizing contribution of heating and flow shear,the 2/1 TM can be completely suppressed. 展开更多
关键词 tearing mode electron cyclotron resonant heating tearing mode suppression
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Control of 2-D Semi-Markov Jump Systems:A View from Mode Generation Mechanism
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作者 Yunzhe Men Jian Sun Jie Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期258-260,共3页
Dear Editor,Two-dimensional(2-D) systems have wide applications in image data processing,gas absorption and fluid dynamics analysis [1]-[3].When there exist abrupt changes in 2-D systems,they are usually modeled by 2-... Dear Editor,Two-dimensional(2-D) systems have wide applications in image data processing,gas absorption and fluid dynamics analysis [1]-[3].When there exist abrupt changes in 2-D systems,they are usually modeled by 2-D Markov jump systems(MJSs) or 2-D semi-Markov jump systems(SMJSs).This letter investigates the control of 2-D SMJSs based on a novel mode generation mechanism,which could avoid mode ambiguousness phenomenon caused by the evolution of system mode in two different directions.The criterion that guarantees the almost surely exponential stability of the system is obtained.A thermal process is studied to demonstrate the availability of the proposed method. 展开更多
关键词 MARKOV mode system
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Influences of Co-Flow and Counter-Flow Modes of Reactant Flow Arrangement on a PEMFC at Start-Up
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作者 Qianqian Shao Min Wang Nuo Xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1337-1356,共20页
To investigate the influences of co-flowand counter-flowmodes of reactant flowarrangement on a proton exchange membrane fuel cell(PEMFC)during start-up,unsteady physical and mathematical models fully coupling the flow... To investigate the influences of co-flowand counter-flowmodes of reactant flowarrangement on a proton exchange membrane fuel cell(PEMFC)during start-up,unsteady physical and mathematical models fully coupling the flow,heat,and electrochemical reactions in a PEMFC are established.The continuity equation and momentum equation are solved by handling pressure-velocity coupling using the SIMPLE algorithm.The electrochemical reaction rates in the catalyst layers(CLs)of the cathode and anode are calculated using the Butler-Volmer equation.The multiphase mixture model describes the multiphase transport process of gas mixtures and liquid water in the fuel cell.After validation,the influences of co-flow and counter-flow modes on the PEMFC performance are investigated,including the evolution of the current density,flow field,temperature field,and reactant concentration field during start-up,as well as the steady distribution of the current density,reactant concentration,andmembrane water content when the start-up stabilizes.Co-flow and counter-flow modes influence the current density distribution and temperature distribution.On the one hand,the co-flow mode accelerates the start-up process of the PEMFC and leads to a more evenly distributed current density than the counter-flow mode.On the other hand,the temperature difference between the inlet and outlet sections of the cell is up to 10.1℃ under the co-flow mode,much larger than the 5.0℃ observed in the counter-flow mode.Accordingly,the counter-flowmode results in a more evenly distributed temperature and a lower maximum temperature than the co-flow case.Therefore,in the flow field design of a PEMFC,the reactant flow arrangements can be considered to weigh between better heat management and higher current density distribution of the cell. 展开更多
关键词 PEMFC full coupling model Butler-Volmer equation multiphase mixture model co-flow mode counter-flow mode
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Investigation on the roles of equilibrium toroidal rotation during edge-localized mode mitigated by resonant magnetic perturbations
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作者 董良康 陈少永 +3 位作者 牟茂淋 罗杨 秦晨晨 唐昌建 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第1期16-33,共18页
The effects of equilibrium toroidal rotation during edge-localized mode(ELM)mitigated by resonant magnetic perturbation(RMP)are studied with the experimental equilibria of the EAST tokamak based on the four-field mode... The effects of equilibrium toroidal rotation during edge-localized mode(ELM)mitigated by resonant magnetic perturbation(RMP)are studied with the experimental equilibria of the EAST tokamak based on the four-field model in the BOUT++code.As the two main parameters to determine the toroidal rotation profiles,the rotation shear and magnitudes were separately scanned to investigate their roles in the impact of RMPs on peeling-ballooning(P-B)modes.On one hand,the results show that strong toroidal rotation shear is favorable for the enhancement of the self-generated E×B shearing rate<ω_(E×B)>with RMPs,leading to significant ELM mitigation with RMP in the stronger toroidal rotation shear region.On the other hand,toroidal rotation magnitudes may affect ELM mitigation by changing the penetration of the RMPs,more precisely the resonant components.RMPs can lead to a reduction in the pedestal energy loss by enhancing the multimode coupling in the turbulence transport phase.The shielding effects on RMPs increase with the toroidal rotation magnitude,leading to the enhancement of the multimode coupling with RMPs to be significantly weakened.Hence,the reduction in pedestal energy loss by RMPs decreased with the rotation magnitude.In brief,the results show that toroidal rotation plays a dual role in ELM mitigation with RMP by changing the shielding effects of plasma by rotation magnitude and affecting<ω_(E×B)>by rotation shear.In the high toroidal rotation region,toroidal rotation shear is usually strong and hence plays a dominant role in the influence of RMP on P-B modes,whereas in the low rotation region,toroidal rotation shear is weak and has negligible impact on P-B modes,and the rotation magnitude plays a dominant role in the influence of RMPs on the P-B modes by changing the field penetration.Therefore,the dual role of toroidal rotation leads to stronger ELM mitigation with RMP,which may be achieved both in the low toroidal rotation region and the relatively high rotation region that has strong rotational shear. 展开更多
关键词 edge-localized mode peeling–ballooning modes resonant magnetic perturbation toroidal rotation plasma response TOKAMAK
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Dissipative soliton resonance within different dispersion regimes in a single mode-locked laser
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作者 赵哲韬 舒沁珂 +6 位作者 解梓怡 任俞宣 张颖 袁博 赵春勃 彭俊松 曾和平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期368-372,共5页
Dissipative soliton resonance(DSR) was previously studied in separated mode-locked fiber lasers within different dispersion regimes including anomalous, near-zero and normal dispersion. Here we propose a method to stu... Dissipative soliton resonance(DSR) was previously studied in separated mode-locked fiber lasers within different dispersion regimes including anomalous, near-zero and normal dispersion. Here we propose a method to study DSR in a single mode-locked laser in these different dispersion regimes. This is achieved by virtue of a waveshaper which can control the laser dispersion readily using software, avoiding the usual tedious cutback method. We find that dispersion has a negligible effect on DSR since the pulse duration keeps constant while dispersion is varied. Moreover, we examine the dynamics of DSR on the parameters of the SA including modulation depth and saturation power, and find that the pulse duration can be changed in a large range when the saturation power is decreased. Our numerical simulations could be important to guide relative experimental studies. 展开更多
关键词 mode locking LASER FIBER PULSE
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On the generation of high-quality Nyquist pulses in mode-locked fiber lasers
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作者 任俞宣 葛锦蔓 +2 位作者 李小军 彭俊松 曾和平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期424-427,共4页
Nyquist pulses have wide applications in many areas,from electronics to optics.Mode-locked lasers are ideal platforms to generate such pulses.However,how to generate high-quality Nyquist pulses in mode-locked lasers r... Nyquist pulses have wide applications in many areas,from electronics to optics.Mode-locked lasers are ideal platforms to generate such pulses.However,how to generate high-quality Nyquist pulses in mode-locked lasers remains elusive.We address this problem by managing different physical effects in mode-locked fiber lasers through extensive numerical simulations.We find that net dispersion,linear loss,gain and filter shaping can affect the quality of Nyquist pulses significantly.We also demonstrate that Nyquist pulses experience similariton shaping due to the nonlinear attractor effect in the gain medium.Our work may contribute to the design of Nyquist pulse sources and enrich the understanding of pulse shaping dynamics in mode-locked lasers. 展开更多
关键词 mode locking laser SOLITON FIBER PULSE
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Effects of diamagnetic drift on nonlinear interaction between multi-helicity neoclassical tearing modes
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作者 王海源 姜帅 +3 位作者 刘桐 魏来 栾其斌 王正汹 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期452-458,共7页
A numerical study of the diamagnetic drift effect on the nonlinear interaction between multi-helicity neoclassical tearing modes(NTMs) is carried out using a set of four-field equations including two-fluid effects.The... A numerical study of the diamagnetic drift effect on the nonlinear interaction between multi-helicity neoclassical tearing modes(NTMs) is carried out using a set of four-field equations including two-fluid effects.The results show that,in contrast to the single-fluid case,5/3 NTM cannot be completely suppressed by 3/2 NTM with diamagnetic drift flow.Both modes exhibit oscillation and coexist in the saturated phase.To better understand the effect of the diamagnetic drift flow on multiple-helicity NTMs,the influence of typical relevant parameters is investigated.It is found that the average saturated magnetic island width increases with increasing bootstrap current fraction f_(b) but decreases with the ion skin depth δ.In addition,as the ratio of parallel to perpendicular transport coefficients χ_(‖)/χ_(⊥) increases,the average saturated magnetic island widths of the 3/2 and 5/3 NTMs increase.The underlying mechanisms behind these observations are discussed in detail. 展开更多
关键词 TOKAMAK TWO-FLUID neoclassical tearing modes multi-helicity
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Constraint on the focal mechanism of the 2011 Tohoku earthquake from the radial modes
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作者 Weikun Chen Hao Ding 《Geodesy and Geodynamics》 EI CSCD 2024年第1期27-32,共6页
Different from other normal modes of the Earth’s free oscillation that depend on all the six components(M_(rr),M_(tt),M_(pp),M_(rt),M_(rp),and M_(tp))of the centroid moment tensor,the amplitudes of the radial modes d... Different from other normal modes of the Earth’s free oscillation that depend on all the six components(M_(rr),M_(tt),M_(pp),M_(rt),M_(rp),and M_(tp))of the centroid moment tensor,the amplitudes of the radial modes depend on the M_(rr)component(e.g.,scalar moment(M_(0)),dip(δ),and slip(λ))and hypocenter depth of the focal mechanism,and hence can be easily used to constrain these parameters of the focal mechanism.In this study,we use the superconducting gravimeter(SG)records after the 2011 Tohoku earthquake to analyze the radial modes_(0)S_(0)and_(1)S_(0).Based on the solutions of the focal mechanism provided by the GCMT and USGS,we can obtain the theoretical amplitudes of these two radial modes.Comparing the theoretical amplitudes with the observation amplitudes,it is found that there are obvious differences between the former and the latter,which means that the GCMT and USGS focal mechanisms cannot well represent the real focal mechanism of the 2011 event.Taking the GCMT solution as a reference and changing the depth and the three parameters of the M_(rr)moment,the scalar moment(M_(0))and the dip(δ)have significant influences,but the effects of the slip(λ)and the depth are minor.After comparisons,we provide a new constraint(M_(0)=5.8±0.09×10^(22)N·m,δ=10.1±0.08°,λ=88°,and depth=20 km)for the focal mechanism of the 2011 event.In addition,we further determine the center frequency(1.631567±2.6e^(-6)mHz)and quality factor(2046.4±50.1)of the_(1)S_(0)mode. 展开更多
关键词 Focal mechanism Radial modes Gravity observation
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Observation of Doppler shift f_(D) modulated by the internal kink mode using conventional reflectometry in the EAST tokamak
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作者 李恭顺 张涛 +18 位作者 耿康宁 文斐 叶凯萱 徐立清 朱翔 张学习 钟富彬 周振 杨书琪 周子强 喻琳 兰婷 王守信 提昂 张寿彪 刘海庆 李国强 高翔 the EAST Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期1-9,共9页
In this paper we present a new experimental observation using a conventional reflectometry technique,poloidal correlation reflectometry(PCR),in the Experimental Advanced Superconducting Tokamak(EAST).The turbulence sp... In this paper we present a new experimental observation using a conventional reflectometry technique,poloidal correlation reflectometry(PCR),in the Experimental Advanced Superconducting Tokamak(EAST).The turbulence spectrum detected by the PCR system exhibits an asymmetry and induced Doppler shift f_(D)during the internal kink mode(IKM)rotation phase.This Doppler shift f_(D)is the target measurement of Doppler reflectometry,but captured by conventional reflectometry.Results show that the Doppler shift f_(D)is modulated by the periodic changes in the effective angle between the probing wave and cutoff layer normal,but not by plasma turbulence.The fishbone mode and saturated long-lived mode are typical IKMs,and this modulation phenomenon is observed in both cases.Moreover,the value of the Doppler shift f_(D)is positively correlated with the amplitude of the IKM,even when the latter is small.However,the positive and negative frequency components of the Doppler shift f_(D)can be asymmetric,which is related to the plasma configuration.A simulated analysis is performed by ray tracing to verify these observations.These results establish a clear link between f_(D)and IKM rotation,and are helpful for studying the characteristics of IKM and related physical phenomena. 展开更多
关键词 microwave reflectometry Doppler shift internal kink mode
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Generation of lossy mode resonances(LMR)using perovskite nanofilms
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作者 Dayron Armas Ignacio R.Matias +4 位作者 M.Carmen Lopez-Gonzalez Carlos Ruiz Zamarreño Pablo Zubiate Ignacio del Villar Beatriz Romero 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第2期33-40,共8页
The results presented here show for the first time the experimental demonstration of the fabrication of lossy mode resonance(LMR) devices based on perovskite coatings deposited on planar waveguides. Perovskite thin fi... The results presented here show for the first time the experimental demonstration of the fabrication of lossy mode resonance(LMR) devices based on perovskite coatings deposited on planar waveguides. Perovskite thin films have been obtained by means of the spin coating technique and their presence was confirmed by ellipsometry, scanning electron microscopy, and X-ray diffraction testing. The LMRs can be generated in a wide wavelength range and the experimental results agree with the theoretical simulations. Overall, this study highlights the potential of perovskite thin films for the development of novel LMR-based devices that can be used for environmental monitoring, industrial sensing, and gas detection, among other applications. 展开更多
关键词 PEROVSKITE thin films slab waveguide lossy mode resonance
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