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From Control to Empowerment:A Paradigm Shift in the Discourse of Educational Supervision
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作者 Jinhua Zhou Kai Zhang 《Journal of Contemporary Educational Research》 2024年第9期176-180,共5页
As educational reforms intensify and societal emphasis shifts towards empowerment,the traditional discourse paradigm of management and control in educational supervision faces growing challenges.This paper explores th... As educational reforms intensify and societal emphasis shifts towards empowerment,the traditional discourse paradigm of management and control in educational supervision faces growing challenges.This paper explores the transformation of this discourse paradigm through the lens of empowerment,analyzing its distinct characteristics,potential pathways,and effective strategies.This paper begins by reviewing the concept of empowerment and examining the current research landscape surrounding the discourse paradigm in educational supervision.Subsequently,we conduct a comparative analysis of the“control”and“empowerment”paradigms,highlighting their essential differences.This analysis illuminates the key characteristics of an empowerment-oriented approach to educational supervision,particularly its emphasis on dialogue,collaboration,participation,and,crucially,empowerment itself.Ultimately,this research advocates for a shift in educational supervision towards an empowerment-oriented discourse system.This entails a multi-pronged approach:transforming ingrained beliefs,embracing renewed pedagogical concepts,fostering methodological innovation,and optimizing existing mechanisms and strategies within educational supervision.These changes are proposed to facilitate the more effective alignment of educational supervision with the pursuit of high-quality education. 展开更多
关键词 Educational supervision paradigm shift CONTROL EMPOWERMENT
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Innovative Scientific Discoveries:The Role of Intelligent Computing in the Fifth Paradigm Shift
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作者 Zhiyi Liu 《Journal of Electronic Research and Application》 2024年第5期174-178,共5页
This article explores the key role of intelligent computing in driving the paradigm shift of scientific discovery.The article first outlines the five paradigms of scientific discovery,from empirical observation to the... This article explores the key role of intelligent computing in driving the paradigm shift of scientific discovery.The article first outlines the five paradigms of scientific discovery,from empirical observation to theoretical models,then to computational simulation and data intensive science,and finally introduces intelligent computing as the core of the fifth paradigm.Intelligent computing enhances the ability to understand,predict,and automate scientific discoveries of complex systems through technologies such as deep learning and machine learning.The article further analyzes the applications of intelligent computing in fields such as bioinformatics,astronomy,climate science,materials science,and medical image analysis,demonstrating its practical utility in solving scientific problems and promoting knowledge development.Finally,the article predicts that intelligent computing will play a more critical role in future scientific research,promoting interdisciplinary integration,open science,and collaboration,providing new solutions for solving complex problems. 展开更多
关键词 Fifth paradigm General artificial intelligence Intelligent computing
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The Paradigm Shift in Language Learning in China
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作者 张玲 《语言与文化研究》 2008年第2期126-130,共5页
With the development of English as an international language,English speakers are widely spread in the world.The English learning fashion has been greatly changed since the culture background of English as a langauge ... With the development of English as an international language,English speakers are widely spread in the world.The English learning fashion has been greatly changed since the culture background of English as a langauge has shifted to a mixed cultures instead of just British and American. But the standard varieties of British and American English have been accepted as the only generally accepted forms of standard English in China.The language learning fashion in China is about to undertake a big paradigm shift.This paper is an analysis of the English learning pattern shift in Chinese setting and therefore suggests a practical activities to apply this concept in English learning classes. 展开更多
关键词 paradigm shift china MOTHER Tongue(MT) in-class ac
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Extraction of methane hydrate energy by carbon dioxide injection-key challenges and a paradigm shift 被引量:7
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作者 Peter Englezos 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第9期2044-2048,共5页
Significant effort including field work has been devoted to develop a natural gas extraction technology from natural gas hydrate reservoirs through the injection of carbon dioxide. Natural gas hydrate is practically m... Significant effort including field work has been devoted to develop a natural gas extraction technology from natural gas hydrate reservoirs through the injection of carbon dioxide. Natural gas hydrate is practically methane hydrate. The hypothesis is that carbon dioxide will be stored as hydrate owing to its favorable stability conditions compared to methane hydrate. Although the dynamics of the CO2/CH4 exchange process are not entirely understood it is established that the exchange process is feasible. The extent is limited but even if the CH4 recovery is optimized there is a need for a CH4/CO2 separation plant to enable a complete cyclic sequence of CO2 capture, injection and CH4 recovery. In this paper we propose an alternative paradigm to the Inject(CO2)/Exchange with(CH4)/Recover(CH4) one namely Recover(CH4) first and then Inject(CO2) for Storage. 展开更多
关键词 CARBON dioxide HYDRATE Methane HYDRATE CARBON storage CARBON SEQUESTRATION ENERGY paradigm shift
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Mean Shift跟踪算法创新实验项目设计
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作者 王辉 王雪莹 于立君 《实验室科学》 2024年第1期12-16,共5页
视频跟踪算法是计算机视觉实践课程中比较受关注的实验项目。针对突变情况下传统Mean Shift跟踪算法无法实时准确跟踪的问题,设计了基于模板更新和线性预估的Mean Shift跟踪算法创新实验项目。在模板更新策略下,引入背景模板,通过将原... 视频跟踪算法是计算机视觉实践课程中比较受关注的实验项目。针对突变情况下传统Mean Shift跟踪算法无法实时准确跟踪的问题,设计了基于模板更新和线性预估的Mean Shift跟踪算法创新实验项目。在模板更新策略下,引入背景模板,通过将原目标模板和背景模板与设定的阈值进行比较来对干扰因素进行判定,当干扰因素判定目标受到遮挡时,引入线性预估方程进行目标位置预测,有效解决目标在遮挡情况下跟踪丢失的问题。通过对测试视频的跟踪效果和性能进行对比分析,验证了算法在突变情况下相较于传统算法具有更好的抗干扰能力。以算法创新设计为核心,通过开放性创新实验项目的选题、设计、答辩、反馈的闭环实验过程,有效提高了学生算法创新设计能力。 展开更多
关键词 Mean shift跟踪算法 模板更新 线性预估 抗干扰
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DAO to HANOI via DeSci: AI Paradigm Shifts from AlphaGo to ChatGPT 被引量:16
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作者 Qinghai Miao Wenbo Zheng +3 位作者 Yisheng Lv Min Huang Wenwen Ding Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第4期877-897,共21页
From AlphaGo to ChatGPT,the field of AI has launched a series of remarkable achievements in recent years.Analyzing,comparing,and summarizing these achievements at the paradigm level is important for future AI innovati... From AlphaGo to ChatGPT,the field of AI has launched a series of remarkable achievements in recent years.Analyzing,comparing,and summarizing these achievements at the paradigm level is important for future AI innovation,but has not received sufficient attention.In this paper,we give an overview and perspective on machine learning paradigms.First,we propose a paradigm taxonomy with three levels and seven dimensions from a knowledge perspective.Accordingly,we give an overview on three basic and twelve extended learning paradigms,such as Ensemble Learning,Transfer Learning,etc.,with figures in unified style.We further analyze three advanced paradigms,i.e.,AlphaGo,AlphaFold and ChatGPT.Second,to enable more efficient and effective scientific discovery,we propose to build a new ecosystem that drives AI paradigm shifts through the decentralized science(DeSci)movement based on decentralized autonomous organization(DAO).To this end,we design the Hanoi framework,which integrates human factors,parallel intelligence based on a combination of artificial systems and the natural world,and the DAO to inspire AI innovations. 展开更多
关键词 ChatGPT decentralized science(DeSci) decentralized autonomous organization(DAO) machine learning paradigm shift
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Paradigm Shifts or Methodology Changes ? Think Twice Before You Put Paradigms into Practice 被引量:1
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作者 Cormspondence: Yang Yonglin,Department Of Foreign Languages,Tsinghua University Beliing,P. R. China 《现代外语》 CSSCI 北大核心 1999年第4期420-420,共1页
ThepresentpaperaddressestheapplicabilityofKuhn'stheoryofparadigmshiftsandscientificrevolutionstothefieldoflanguageteaching.First,itillustratestheconceptionofparadigmshiftsandscientificrevolutions.Andthen,itsetsupt... ThepresentpaperaddressestheapplicabilityofKuhn'stheoryofparadigmshiftsandscientificrevolutionstothefieldoflanguageteaching.First,itillustratestheconceptionofparadigmshiftsandscientificrevolutions.Andthen,itsetsuptwotestsforexaminingtheissueofwhetherK... 展开更多
关键词 linguistic theory PSYCHOLOGY paradigm shiftS scientific REVOLUTIONS language teaching ECLECTICISM METHODOLOGY
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长三角城市群经济韧性测度与分析——基于Shift-Share的经济韧性分解
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作者 王欢芳 陈素月 《兰州财经大学学报》 2024年第2期48-61,共14页
以长三角城市群27个城市为研究对象,测度2008—2010年抵抗期和2010—2019年恢复期城市群经济韧性水平,并进一步运用Shift-Share分解方法探索长三角城市群经济韧性内在影响机制。研究显示:抵抗期和恢复期中长三角城市群经济韧性均值分别... 以长三角城市群27个城市为研究对象,测度2008—2010年抵抗期和2010—2019年恢复期城市群经济韧性水平,并进一步运用Shift-Share分解方法探索长三角城市群经济韧性内在影响机制。研究显示:抵抗期和恢复期中长三角城市群经济韧性均值分别为0.309和0.301,均强于全国层面经济韧性水平;Shift-Share分解后发现竞争力分量对各城市经济韧性水平提升起到决定性作用,抵抗期阶段主要由第二、三产业共同作用影响经济韧性水平;恢复期阶段则以第二产业竞争力为主导力量,同时以第三产业竞争力作为辅助力量。通过实证探究长三角城市群经济一体化发展的规律和特点,为增强中国经济韧性提出相关建议,助力中国经济高质量发展。 展开更多
关键词 长三角城市群 经济韧性 shift-Share分解 产业结构 竞争力
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Paradigm Shift in Urban-rural Integration in the Context of China
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作者 Chang GAO Xu ZHAO 《Asian Agricultural Research》 2018年第9期41-45,52,共6页
This paper presents a discussion about paradigm shift from following aspects: the paradigm shift and sustainability,traditional paradigm in China,experience from developed countries and the new planning paradigm shift... This paper presents a discussion about paradigm shift from following aspects: the paradigm shift and sustainability,traditional paradigm in China,experience from developed countries and the new planning paradigm shift. Also,the paper mainly focuses on the topic of urbanrural relationship in China and argues the possibility of paradigm shift to achieve urban-rural integration. The traditional urbanization paradigm has city-oriented policy and always focuses on industrialization to promote urbanization,which leads to the village hollowing and many other sacrifices in rural areas. Thus,new shifting of the urban-rural integration is essential. The paper mentions the new planning from policy and spatial aspects appearing some ways to achieve the new paradigm shift in urban-rural integration. 展开更多
关键词 可持续性 城市化 发展现状 经济发展
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The Paradigm Shifts in Bangladesh and China Relations in the New Global Political Architecture
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作者 Shahab Enam Khan 《Contemporary International Relations》 2017年第1期117-132,共16页
Chinese President Xi Jinping's visit to Bangladesh in October2016 has dramatically uplifted the strategic value of Bangladesh to the world and presented new opportunities to Bangladeshs' security,political and... Chinese President Xi Jinping's visit to Bangladesh in October2016 has dramatically uplifted the strategic value of Bangladesh to the world and presented new opportunities to Bangladeshs' security,political and economic interests.Bangladesh and China have agreed to elevate‘the closer comprehensive partnership of cooperation'to a ‘strategic partnership'.China's B&R initiative is perhaps a major project for Bangladesh to promote economic development and to connect itself with global markets. 展开更多
关键词 Bangladesh-China relations B&R paradigm shifts
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Information Technology and Paradigm Shifting in Organizational Structure and Strategy
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作者 WU XiaoboZhejiang University, Hangzhou 310027, P. R. China HU XiangpeiHarbin Institute of Technology, Harbin 150001, P.R.ChinaDONG ZhiqiangBeijing University of Aeronautics & Astronautics, Beijing 10083, P.R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1994年第4期40-49,共10页
This paper examines the impacts of information technology (IT) on LDCs' competitive conditions, especially the impacts on intra-organization's linkage and technology capability formation via innovation, as the... This paper examines the impacts of information technology (IT) on LDCs' competitive conditions, especially the impacts on intra-organization's linkage and technology capability formation via innovation, as the rising of the new paradigms of system integration. And some strategic implications are made. 展开更多
关键词 Information technology paradigm INNOVATION Organizational structure.
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Learner Autonomy and Attribution: A Paradigm Shift in ELT in India
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作者 J. John Sekar 《Sino-US English Teaching》 2013年第8期583-592,共10页
Learner autonomy and attribution impact English language acquisition. Learners should be encouraged to take the responsibility for their success or failure, and achievement or underperformance in the acquisition of En... Learner autonomy and attribution impact English language acquisition. Learners should be encouraged to take the responsibility for their success or failure, and achievement or underperformance in the acquisition of English as an L2 (second language). A paradigm shift can be visible on the part of teachers and students of English only when they are metamorphosed voluntarily into classroom facilitators and autonomous learners with changed duties and responsibilities. As facilitators, teachers closely monitor learners' attributions to their success/failure in English language courses. "Attribution" means "how learners learn about themselves and order uncertain environments". Teachers are very often unaware of learner attributions; so it becomes essential for them to increase their awareness of learner attributions so that they can become facilitators. Interaction is the only medium for acquisition of English in the classroom, and teachers can play the role of a catalyst only when they allow students to become leamers with autonomy and right kind of learner attributions. Autonomy implies accountability. Very often, learner attributions clash with teacher attributions. As long as there is a clash, teachers can never claim themselves as facilitators of learning. This paper identifies the attributions of Indian learners of English, and studies if they clash with those of teachers. It also finds out the means of minimizing the negative and undesirable attributions of both facilitators and learners. Two standardized research questionnaires were developed and administered among students and teachers to identify the attributions, and to detect the desirability and feasibility of learner autonomy in the Indian context. 展开更多
关键词 paradigm shift learner autonomy leamer attributions FACILITATOR LEARNER self-access center
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High-Precision Doppler Frequency Estimation Based Positioning Using OTFS Modulations by Red and Blue Frequency Shift Discriminator 被引量:1
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作者 Shaojing Wang Xiaomei Tang +3 位作者 Jing Lei Chunjiang Ma Chao Wen Guangfu Sun 《China Communications》 SCIE CSCD 2024年第2期17-31,共15页
Orthogonal Time Frequency and Space(OTFS) modulation is expected to provide high-speed and ultra-reliable communications for emerging mobile applications, including low-orbit satellite communications. Using the Dopple... Orthogonal Time Frequency and Space(OTFS) modulation is expected to provide high-speed and ultra-reliable communications for emerging mobile applications, including low-orbit satellite communications. Using the Doppler frequency for positioning is a promising research direction on communication and navigation integration. To tackle the high Doppler frequency and low signal-to-noise ratio(SNR) in satellite communication, this paper proposes a Red and Blue Frequency Shift Discriminator(RBFSD) based on the pseudo-noise(PN) sequence.The paper derives that the cross-correlation function on the Doppler domain exhibits the characteristic of a Sinc function. Therefore, it applies modulation onto the Delay-Doppler domain using PN sequence and adjusts Doppler frequency estimation by red-shifting or blue-shifting. Simulation results show that the performance of Doppler frequency estimation is close to the Cramér-Rao Lower Bound when the SNR is greater than -15dB. The proposed algorithm is about 1/D times less complex than the existing PN pilot sequence algorithm, where D is the resolution of the fractional Doppler. 展开更多
关键词 channel estimation communication and navigation integration Orthogonal Time Frequency and Space pseudo-noise sequence red-blue frequency shift discriminator
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基于自适应核带宽度Mean Shift算法的单木识别研究
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作者 马秀 陈伟 +2 位作者 徐雁南 张舒 王国宏 《森林工程》 北大核心 2024年第2期92-101,126,共11页
为提高多树种森林中单木识别的精度,利用机载激光雷达点云数据作为研究对象,提出一种基于自适应核带宽度Mean Shift算法的单木识别方法。该方法先采用直方图分析法分离树冠点云和冠层下点云,再采用基于二维增量网格投影的区域生长法,估... 为提高多树种森林中单木识别的精度,利用机载激光雷达点云数据作为研究对象,提出一种基于自适应核带宽度Mean Shift算法的单木识别方法。该方法先采用直方图分析法分离树冠点云和冠层下点云,再采用基于二维增量网格投影的区域生长法,估算单木冠幅有效半径,然后以单木冠幅有效半径作为自适应核带宽度,对树冠点云进行自适应Mean Shift聚类分析,得到树冠点簇,最后采用包络盒方法根据树冠点簇和树干点云的空间关系识别单木。试验结果表明,检测树与实际树的位置、树冠形态近似一致,单木召回率达到86.1%,准确率达到91.5%,高于2个对比试验的结果。研究证明设置的自适应核带宽度能够自动调整以反映局部树冠的实际大小,在多树种森林的单木识别中表现良好。 展开更多
关键词 激光雷达 单木识别 Mean shift算法 核带宽度 自适应
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Unveiling the challenges encountered by newly graduated nurses during night shifts:A descriptive qualitative study
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作者 Naomi Kisanuki Miyuki Takase Masako Yamamoto 《International Journal of Nursing Sciences》 CSCD 2024年第4期447-456,共10页
Objectives:Newly graduated nurses commence night shifts during a phase of heightened vulnerability to reality shock,exacerbating the challenges faced by these graduates.Therefore,this study aimed to identify the chall... Objectives:Newly graduated nurses commence night shifts during a phase of heightened vulnerability to reality shock,exacerbating the challenges faced by these graduates.Therefore,this study aimed to identify the challenges experienced by newly graduated nurses when undertaking night shifts in order to help identify a strategy for supporting their adaptation to these shifts.Methods:Semi-structured personal interviews were used to collect data.Fifteen newly graduated nurses were selected to participate in the study by purposive sampling method from November 2021 to March 2022 in one of four general hospitals situated in the southwestern region of Japan.Semi-structured interviews were analyzed by using thematic analysis.Results:The analysis revealedfive central themes and nine subthemes:challenges in task efficiency(task organization challenges,challenges in time-constrained task performance),challenges in responding to patients’changing conditions(challenges in responding to patients’irregular conditions,challenges in responding to nighttime changes in patients’behaviors),challenges in independent practice(challenges in engaging in independent nursing practice,challenges in dealing with unexpected events),challenges in establishing collaborative relationships(challenges in working closely with other staff,challenges in establishing collaborative relationships during night shifts with limited resources),challenges in adapting to shift work(challenges in managing physical conditions for shift work).Conclusions:Newly graduated nurses often encounter challenges in performing their tasks during the transition period.When working night shifts,they face additional hurdles unique to nocturnal duties.Thefindings underscore the necessity for these graduates to develop night shift-specific readiness to effectively navigate the demands inherent in such work schedules. 展开更多
关键词 CHALLENGE Newly graduated nurses Patient care management Qualitative research shift work schedule Night shifts
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THE PERSISTENCE OF SOLUTIONS IN A NONLOCAL PREDATOR-PREY SYSTEM WITH A SHIFTING HABITAT
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作者 赵敏 袁荣 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期1096-1114,共19页
In this paper,we mainly study the propagation properties of a nonlocal dispersal predator-prey system in a shifting environment.It is known that Choi et al.[J Differ Equ,2021,302:807-853]studied the persistence or ext... In this paper,we mainly study the propagation properties of a nonlocal dispersal predator-prey system in a shifting environment.It is known that Choi et al.[J Differ Equ,2021,302:807-853]studied the persistence or extinction of the prey and of the predator separately in various moving frames.In particular,they achieved a complete picture in the local diffusion case.However,the question of the persistence of the prey and of the predator in some intermediate moving frames in the nonlocal diffusion case was left open in Choi et al.'s paper.By using some a prior estimates,the Arzelà-Ascoli theorem and a diagonal extraction process,we can extend and improve the main results of Choi et al.to achieve a complete picture in the nonlocal diffusion case. 展开更多
关键词 predator-prey system PERSISTENCE nonlocal dispersal shifting environment
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IUINet:基于Shift的双流映射3D医学分割模型
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作者 朱庚鑫 程远志 刘豪 《计算机系统应用》 2024年第1期141-147,共7页
为了提高特征融合,我们设计了动态全连接层(DyFC),该方法重新定义了权重和偏置,使用基向量来代表新的权重和偏置,基向量的系数是根据每一个输入特征进行学习得到的,权重和偏置不再是共享的,而是特有的,这对于每一个特征的表达更具有专向... 为了提高特征融合,我们设计了动态全连接层(DyFC),该方法重新定义了权重和偏置,使用基向量来代表新的权重和偏置,基向量的系数是根据每一个输入特征进行学习得到的,权重和偏置不再是共享的,而是特有的,这对于每一个特征的表达更具有专向性.在本文中,我们提出了一种双流映射结构模型IUINet.IUINet是通过3DShift操作、空间可分离卷积的组合来实现医学图像分割任务,同时保持精度和效率之间的平衡.所提出来的IUINet遵循编码器-解码器结构,其中编码器一部分包含Shift操作、逐点Conv1×1操作,另一部分包含空间可分离卷积操作.IUINet运用了多尺度输入以及多尺度特征映射层,提高反向传播速度,降低反向传播的平均距离.提高模型的精确度,增加模型泛化能力,减少过拟合. 展开更多
关键词 shift 基向量 动态全连接层 医学图像分割
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Tunable spectral continuous shift of high-order harmonic generation in atoms by a plasmon-assisted shaping pulse
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作者 王源 李玉龙 +7 位作者 乔月 高娜 郭福明 陈洲 赫兰海 杨玉军 赵曦 王俊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期433-440,共8页
We delve into the phenomenon of high-order harmonic generation within a helium atom under the influence of a plasmon-assisted shaping pulse.Our findings reveal an intriguing manipulation of the frequency peak position... We delve into the phenomenon of high-order harmonic generation within a helium atom under the influence of a plasmon-assisted shaping pulse.Our findings reveal an intriguing manipulation of the frequency peak position in the harmonic emission by adjusting the absolute phase parameter within the frequency domain of the shaping pulse.This phenomenon holds potential significance for experimental setups necessitating precisely tuned single harmonics.Notably,we observe a modulated shift in the created harmonic photon energy,spanning an impressive range of 1.2 eV.This frequency peak shift is rooted in the asymmetry exhibited by the rising and falling edges of the laser pulse,directly influencing the position of the peak frequency emission.Our study quantifies the dependence of this tuning range and the asymmetry of the laser pulse,offering valuable insights into the underlying mechanisms driving this phenomenon.Furthermore,our investigation uncovers the emergence of semi-integer order harmonics as the phase parameter is altered.We attribute this discovery to the intricate interference between harmonics generated by the primary and secondary return cores.This observation introduces an innovative approach for generating semi-integer order harmonics,thus expanding our understanding of high-order harmonic generation.Ultimately,our work contributes to the broader comprehension of complex phenomena in laser-matter interactions and provides a foundation for harnessing these effects in various applications,particularly those involving precise spectral control and the generation of unique harmonic patterns. 展开更多
关键词 high-order harmonic semi-integer-order spectra shift inhomogeneous field
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Strong metal-support interactions between highly dispersed Cu^(+) species and ceria via mix-MOF pyrolysis toward promoted water-gas shift reaction
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作者 Xiao-Chen Sun Xing-Chi Li +7 位作者 Ze-Wei Xie Chen-Yue Yuan De-Jiu Wang Qian Zhang Xiao-Yu Guo Hao Dong Hai-Chao Liu Ya-Wen Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期475-483,共9页
The modulation of metal-support interfacial interaction is significant but challenging in the design of high-efficiency and high-stability supported catalysts.Here,we report a synthetic strategy to upgrade Cu-CeO_(2)i... The modulation of metal-support interfacial interaction is significant but challenging in the design of high-efficiency and high-stability supported catalysts.Here,we report a synthetic strategy to upgrade Cu-CeO_(2)interfacial interaction by the pyrolysis of mixed metal-organic framework(MOF)structure.The obtained highly dispersed Cu/CeO_(2)-MOF catalyst via this strategy was used to catalyze water-gas shift reaction(WGSR),which exhibited high activity of 40.5μmolCOgcat^(-1).s^(-1)at 300℃and high stability of about 120 h.Based on comprehensive studies of electronic structure,pyrolysis strategy has significant effect on enhancing metal-support interaction and then stabilizing interfacial Cu^(+)species under reaction conditions.Abundant Cu^(+)species and generated oxygen vacancies over Cu/CeO_(2)-MOF catalyst played a key role in CO molecule activation and H2O molecule dissociation,respectively.Both collaborated closely and then promoted WGSR catalytic performance in comparison with traditio nal supported catalysts.This study shall offer a robust approach to harvest highly dispersed catalysts with finely-tuned metal-support interactions for stabilizing the most interfacial active metal species in diverse heterogeneous catalytic reactions. 展开更多
关键词 Cu-based catalyst MOF derivative Water-gas shift reaction Metal-support interaction
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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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