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Spatial quantum coherent modulation with perfect hybrid vector vortex beam based on atomic medium
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作者 马燕 杨欣 +6 位作者 常虹 杨鑫琪 曹明涛 张晓斐 高宏 董瑞芳 张首刚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期360-364,共5页
The perfect hybrid vector vortex beam(PHVVB)with helical phase wavefront structure has aroused significant concern in recent years,as its beam waist does not expand with the topological charge(TC).In this work,we inve... The perfect hybrid vector vortex beam(PHVVB)with helical phase wavefront structure has aroused significant concern in recent years,as its beam waist does not expand with the topological charge(TC).In this work,we investigate the spatial quantum coherent modulation effect with PHVVB based on the atomic medium,and we observe the absorption characteristic of the PHVVB with different TCs under variant magnetic fields.We find that the transmission spectrum linewidth of PHVVB can be effectively maintained regardless of the TC.Still,the width of transmission peaks increases slightly as the beam size expands in hot atomic vapor.This distinctive quantum coherence phenomenon,demonstrated by the interaction of an atomic medium with a hybrid vector-structured beam,might be anticipated to open up new opportunities for quantum coherence modulation and accurate magnetic field measurement. 展开更多
关键词 perfect hybrid vector vortex beam topological charge quantum coherence optical manipulation
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Perfect 1-k Matchings of Bipartite Graphs
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作者 Wenduan Dai Yan Liu Yanfang Wu 《Open Journal of Discrete Mathematics》 2024年第4期43-53,共11页
Let k be a positive integer and G a bipartite graph with bipartition (X,Y). A perfect 1-k matching is an edge subset M of G such that each vertex in Y is incident with exactly one edge in M and each vertex in X is inc... Let k be a positive integer and G a bipartite graph with bipartition (X,Y). A perfect 1-k matching is an edge subset M of G such that each vertex in Y is incident with exactly one edge in M and each vertex in X is incident with exactly k edges in M. A perfect 1-k matching is an optimal semi-matching related to the load-balancing problem, where a semi-matching is an edge subset M such that each vertex in Y is incident with exactly one edge in M, and a vertex in X can be incident with an arbitrary number of edges in M. In this paper, we give three sufficient and necessary conditions for the existence of perfect 1-k matchings and for the existence of 1-k matchings covering | X |−dvertices in X, respectively, and characterize k-elementary bipartite graph which is a graph such that the subgraph induced by all k-allowed edges is connected, where an edge is k-allowed if it is contained in a perfect 1-k matching. 展开更多
关键词 Bipartite Graph Semi-Matching perfect 1-k Matching k-Elementary Graph
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Using Return and Risk Model for Choosing Perfect Portfolio Applied Study in Cairo Stock Exchange
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作者 Essam Al Arbed 《American Journal of Operations Research》 2024年第1期32-58,共27页
Modern financial theory, commonly known as portfolio theory, provides an analytical framework for the investment decision to be made under uncertainty. It is a well-established proposition in portfolio theory that whe... Modern financial theory, commonly known as portfolio theory, provides an analytical framework for the investment decision to be made under uncertainty. It is a well-established proposition in portfolio theory that whenever there is an imperfect correlation between returns risk is reduced by maintaining only a portion of wealth in any asset, or by selecting a portfolio according to expected returns and correlations between returns. The major improvement of the portfolio approaches over prior received theory is the incorporation of 1) the riskiness of an asset and 2) the addition from investing in any asset. The theme of this paper is to discuss how to propose a new mathematical model like that provided by Markowitz, which helps in choosing a nearly perfect portfolio and an efficient input/output. Besides applying this model to reality, the researcher uses game theory, stochastic and linear programming to provide the model proposed and then uses this model to select a perfect portfolio in the Cairo Stock Exchange. The results are fruitful and the researcher considers this model a new contribution to previous models. 展开更多
关键词 Game Theory Stochastic and Linear Programming perfect Portfolio Portfolio Theory Returns and Risks
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Whole Perfect Vectors and Fermat’s Last Theorem
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作者 Ramon Carbó-Dorca 《Journal of Applied Mathematics and Physics》 2024年第1期34-42,共9页
A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm de... A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm definition, and some vector-specific structures. 展开更多
关键词 Fermat’s Last Theorem Whole perfect Vectors Sine and Cosine Functions Natural and Rational Vectors Fermat Vectors
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The Absence of “Perfect Induction”in the Science
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2024年第5期1930-1947,共18页
The present paper is finalized to show that the Science, even if considered in its two different Phenomenological Approaches at present known, is unable to assert that: “Thinks are like that”. This is because both t... The present paper is finalized to show that the Science, even if considered in its two different Phenomenological Approaches at present known, is unable to assert that: “Thinks are like that”. This is because both the two Scientific Approaches previously mentioned have not the property of “the perfect induction”. Consequently, although they can even reach an experimental confirmation of the theoretical results, and thus a “valid description” of the various phenomena of the surrounding world, such a description has not an “absolute value”. In fact, it always and only has an “operative validity”, that is, it exclusively and solely refers to an “experimental point of view”. This means that such an “operative validity” cannot represent the basis for a logical process characterized by a “perfect induction”. In addition, the Traditional Scientific Approach is also characterized by “Insoluble” Problems, “Intractable Problems”, Problems with “drifts”, which could generally be termed as “side effects”. On the other hand, the same com-possible Scientific Approach based on the Emerging Quality of Self-Organizing Systems, also presents its “Emerging Exits”. Consequently, none of the two mentioned scientific Approaches has the “gift” of “the perfect induction”. However, there are significant differences between the two. Differences that may “suggest” the most appropriate choice among them for an “operative point of view”. This conclusion will be com-proved by considering, with particular reference, both the “side effects”, which are related to the Traditional Approach and, on the other hand, the “Emerging Exits”, which specifically pertain to the new Scientific Approach based on the Emerging Quality of Self-Organizing Systems. 展开更多
关键词 perfect Induction Maximum Ordinality Principle Incipient Differential Calculus
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Practice Makes Perfect
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作者 乔文广 张超(指导) 《中学生英语》 2024年第22期7-7,共1页
All of us know the old saying“Practice makes perfect”.It tells us if we want to realize our goals,we should practice,and one day we will make it.Once I wanted to learn swimming.At first I found it difficult to contr... All of us know the old saying“Practice makes perfect”.It tells us if we want to realize our goals,we should practice,and one day we will make it.Once I wanted to learn swimming.At first I found it difficult to control my body.I just went down into the water.I felt very frightened.Then I watched others who were good at it and asked them the key to success. 展开更多
关键词 perfect perfect saying
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A three-band perfect absorber based on a parallelogram metamaterial slab with monolayer MoS_(2)
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作者 张雯婧 刘青松 +3 位作者 程波 晁明豪 徐云 宋国峰 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期280-285,共6页
As a two-dimensional(2D)material,monolayer MoS2which limits its optical applications has a low absorption efficiency.In this paper,we propose a three-band perfect metamaterial absorber in the visible light range based... As a two-dimensional(2D)material,monolayer MoS2which limits its optical applications has a low absorption efficiency.In this paper,we propose a three-band perfect metamaterial absorber in the visible light range based on monolayer MoS_(2).The peak absorptivity of the structure at each resonance wavelength is nearly perfect,moreover,the light absorption of monolayer MoS2is obviously enhanced at the three resonant wavelengths.The dielectric–dielectric–metal structure we designed produces the coupling of Fabry–Perot resonance and high-order diffraction guided-mode resonance at different absorption peaks,which has been proved by the slab waveguide theory.In addition,the multi-modal absorption phenomenon is explained by extracting the equivalent impedance.The results show that we can adjust the absorption peak wavelength by regulating the parameters of the structure.This structure not only provides an idea for enhancing the interaction between light and two-dimensional materials but also has potential applications for optical detection devices. 展开更多
关键词 METAMATERIAL perfect absorber monolayer MoS_(2) high-order diffraction
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Generation of microwave photon perfect W states of three coupled superconducting resonators
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作者 李新克 周原 +3 位作者 王光辉 吕东燕 Fazal Badshah 黄海铭 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期193-199,共7页
We propose an efficient method for the generation of perfect W states on three microwave superconducting resonators,of which the two nearest neighbors are coupled by a symmetric direct current superconducting quantum ... We propose an efficient method for the generation of perfect W states on three microwave superconducting resonators,of which the two nearest neighbors are coupled by a symmetric direct current superconducting quantum interference device(dc-SQUID).With suitable external magnetic fluxes applied to the dc-SQUID symmetry loops,on-chip tunable interactions between neighboring resonators can be realized,and different perfect W states can be deterministically created on-demand in one step.Numerical simulations show that high-fidelity target states can be generated and our scheme is robust against imperfect parameter tuning and environment-induced decoherence.The present work may have potential applications for implementing quantum computation and quantum information processing based on microwave photons. 展开更多
关键词 quantum entanglement perfect W state circuit QED
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Finite-difference modeling of Maxwell viscoelastic media developed from perfectly matched layer
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作者 Ruo-Long Song 《Petroleum Science》 SCIE EI CSCD 2023年第5期2759-2772,共14页
In numerical simulation of wave propagation,both viscoelastic materials and perfectly matched layers(PMLs)attenuate waves.The wave equations for both the viscoelastic model and the PML contain convolution operators.Ho... In numerical simulation of wave propagation,both viscoelastic materials and perfectly matched layers(PMLs)attenuate waves.The wave equations for both the viscoelastic model and the PML contain convolution operators.However,convolution operator is intractable in finite-difference time-domain(FDTD)method.A great deal of progress has been made in using time stepping instead of convolution in FDTD.To incorporate PML into viscoelastic media,more memory variables need to be introduced,which increases the code complexity and computation costs.By modifying the nonsplitting PML formulation,I propose a viscoelastic model,which can be used as a viscoelastic material and/or a PML just by adjusting the parameters.The proposed viscoelastic model is essentially equivalent to a Maxwell model.Compared with existing PML methods,the proposed method requires less memory and its implementation in existing finite-difference codes is much easier.The attenuation and phase velocity of P-and S-waves are frequency independent in the viscoelastic model if the related quality factors(Q)are greater than 10.The numerical examples show that the method is stable for materials with high absorption(Q=1),and for heterogeneous media with large contrast of acoustic impedance and large contrast of viscosity. 展开更多
关键词 Finite difference Viscoelastic model Nonsplitting perfectly matched layer
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Perfecting the Service Network for Enterprises with Joint Efforts
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作者 Audrey Guo 《China's Foreign Trade》 2023年第1期22-25,共4页
"The year of 2022 marked the70th anniversary of the founding of the China Council for the Promotion of International Trade(CCPIT),and it was also a milestone in the development history of trade promotion.Under th... "The year of 2022 marked the70th anniversary of the founding of the China Council for the Promotion of International Trade(CCPIT),and it was also a milestone in the development history of trade promotion.Under the strong leadership of the Central Committee of the Communist Party of China(CPC) with Comrade Xi Jinping at its core,the national trade promotion system faced up to difficulties,forged ahead. 展开更多
关键词 PROMOTION perfect FOUNDING
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Coherent Perfect Absorption in Higher Order Systems
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作者 Mengjun Fan Linxue Fu +1 位作者 Yaqiong Ding Xinming Fu 《Journal of Applied Mathematics and Physics》 2023年第3期737-745,共9页
We investigate the phenomenon of coherent perfect absorption in a high-order system with three passive resonators coupled to a super-surface to form this three-state coherent perfect absorber. The effective parity tim... We investigate the phenomenon of coherent perfect absorption in a high-order system with three passive resonators coupled to a super-surface to form this three-state coherent perfect absorber. The effective parity time (PT) symmetry in the passive system has received much attention, and in this open three-state PT symmetric system, the incident wave is used as the effective gain instead of balancing the material gain and loss. We analyze the variation of coherent perfect absorption of this system with the coupling coefficient of the system by simulation. 展开更多
关键词 Exceptional Point PT Symmetry Non-Hermitian System Coherent perfect Absorption
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Why Practice Makes Perfect Sense: the Past, Present and Potential Future of the PPP Paradigm in Language Teacher Education
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作者 Jason Anderson 《基础教育外语教学研究》 2023年第2期29-34,共6页
(接上期)Context 3:EFL and ESOL learners at lower levels of achievement The third context relates largely to my own teaching in the adult EFL and ESC OL sectors in the UK,where I make use of PPP with classes of learner... (接上期)Context 3:EFL and ESOL learners at lower levels of achievement The third context relates largely to my own teaching in the adult EFL and ESC OL sectors in the UK,where I make use of PPP with classes of learners that tend towards the following characteristics:1.low levels of overall language proficiency;2.low language learning aptitude;3.low levels of literacy;4.low levels of learner autonomy;5.limited experience of formal classroom study;6.specific educational needs. 展开更多
关键词 OWN perfect FORMAL
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Stability of Perfectly Matched Layers for Time Fractional Schrödinger Equation
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作者 Tingting Zhang Xiangkun Li 《Engineering(科研)》 CAS 2023年第1期1-12,共12页
It is an important issue to numerically solve the time fractional Schrödinger equation on unbounded domains, which models the dynamics of optical solitons propagating via optical fibers. The perfectly matched lay... It is an important issue to numerically solve the time fractional Schrödinger equation on unbounded domains, which models the dynamics of optical solitons propagating via optical fibers. The perfectly matched layer approach is applied to truncate the unbounded physical domain, and obtain an initial boundary value problem on a bounded computational domain, which can be efficiently solved by the finite difference method. The stability of the reduced initial boundary value problem is rigorously analyzed. Some numerical results are presented to illustrate the accuracy and feasibility of the perfectly matched layer approach. According to these examples, the absorption parameters and the width of the absorption layer will affect the absorption effect. The larger the absorption width, the better the absorption effect. There is an optimal absorption parameter, the absorption effect is the best. 展开更多
关键词 Time Fractional Schrödinger Equation perfectly Matched Layer STABILITY
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法院参与涉案企业刑事合规改革十大问题研究 被引量:1
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作者 韩旭 《烟台大学学报(哲学社会科学版)》 CSSCI 2024年第2期67-82,共16页
涉案企业刑事合规改革中法院参与乃必然趋势,各地在理论准备不足、制度缺位的情况下进行改革探索,其困难和困惑自不待言,法官在参与该项工作时的消极态度即是明证。法院如何参与涉案企业合规改革确实是一个值得探讨的问题。这其中的重... 涉案企业刑事合规改革中法院参与乃必然趋势,各地在理论准备不足、制度缺位的情况下进行改革探索,其困难和困惑自不待言,法官在参与该项工作时的消极态度即是明证。法院如何参与涉案企业合规改革确实是一个值得探讨的问题。这其中的重点问题包括法院参与的理论基础、职能作用的发挥、法院开展合规审查考察期的确定、法院进行合规审查适用的案件范围和适用的诉讼阶段、从宽幅度的把握、考察报告的证据属性、法院如何为申请进行合规审查的被拒企业及其责任人提供救济、刑事合规在法院审判中的刑法适用、容错机制的建立、最高人民法院发布指导性案例的必要性等十个方面。对这些问题进行探索,可以为法院参与涉案企业合规改革提供理论支持和参考。 展开更多
关键词 法院 中立性 刑事合规 刑事诉讼法修改 程序完善
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基于金属-介质-金属的可调谐窄带完美吸收的研究
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作者 王晓坤 李周 梁国龙 《中国光学(中英文)》 EI CAS CSCD 北大核心 2024年第2期263-270,共8页
为了实现窄带完美吸收,本文提出了一种简单的三层金-二氧化硅-金薄膜(MDM)结构。通过电磁波时域差分算法(FDTD)进行模拟仿真和理论计算,详细分析了该结构的可调谐吸收特性,同时建立了理论模型,分析了其中存在的电磁模式以及窄带完美吸... 为了实现窄带完美吸收,本文提出了一种简单的三层金-二氧化硅-金薄膜(MDM)结构。通过电磁波时域差分算法(FDTD)进行模拟仿真和理论计算,详细分析了该结构的可调谐吸收特性,同时建立了理论模型,分析了其中存在的电磁模式以及窄带完美吸收的物理机制。首先,利用电磁波时域差分算法和传输矩阵算法(TMM)对该结构进行了理论计算,详细地分析了各个结构参数对吸收光谱的影响。然后,对该结构形成的窄带完美吸收物理机制进行了分析讨论。最后,利用磁控溅射制备手段,成功制备了三层结构的样片。实验观测到的结果与理论仿真一致。实验结果表明:本文提出的窄带完美吸收结构,最窄带宽约为21 nm,最高吸收可达99.51%,基本实现了窄带完美吸收。本文研究成果为相关应用奠定了基础。 展开更多
关键词 薄膜 完美吸收 超薄薄膜
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低相关区互补序列集的构造方法研究
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作者 刘涛 王玉含 李玉博 《电子与信息学报》 EI CAS CSCD 北大核心 2024年第8期3410-3418,共9页
完备互补序列是一类具有理想相关函数性质的信号,在多址接入通信系统、雷达波形设计等领域具有广泛的应用。然而完备互补序列集合大小不超过其子序列数目。为扩展互补序列数目,该文研究了非周期低相关区互补序列集的构造方法,首先提出... 完备互补序列是一类具有理想相关函数性质的信号,在多址接入通信系统、雷达波形设计等领域具有广泛的应用。然而完备互补序列集合大小不超过其子序列数目。为扩展互补序列数目,该文研究了非周期低相关区互补序列集的构造方法,首先提出了两类有限域上的映射函数,进而得到两类参数渐近达到最优的低相关区互补序列集。该类低相关区互补序列集相比完备互补序列集具有更多的序列数目,在通信系统中可支持更多的用户。 展开更多
关键词 完备互补序列 非周期 低相关区 渐近最优
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《焊接机器人技能实训》课程思政的教学研究与探索
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作者 宋丽平 高章虎 +1 位作者 孙登科 杨新华 《电焊机》 2024年第7期144-148,共5页
以智能焊接技术专业《焊接机器人技能实训》课程为例,通过对教学项目的创新设计,实现知识传授、思政教育、素质教育和能力培养的紧密结合。在教学实施过程中,挖掘课程蕴含的思政点,融入“感悟工匠精神,捍卫质量安全,立志技能报国”的思... 以智能焊接技术专业《焊接机器人技能实训》课程为例,通过对教学项目的创新设计,实现知识传授、思政教育、素质教育和能力培养的紧密结合。在教学实施过程中,挖掘课程蕴含的思政点,融入“感悟工匠精神,捍卫质量安全,立志技能报国”的思政主题,有针对性地、以润物细无声的方式将家国情怀、职业精神、人生观、价值观、严谨细致、精益求精的职业理念融入课堂;通过制度来规范学生的行为,通过活动来激励学生的潜能,在学生成长的过程中树立一些榜样,用“榜样”引领他们成长,有效达成了“厚基础、精技能、擅创新”的教学目标。 展开更多
关键词 焊接机器人 课程思政 工匠精神 精益求精
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“行刑”反向衔接的实践难点及对策思考 被引量:2
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作者 王春丽 邓翡斐 沈梦昕 《上海公安学院学报》 2024年第2期79-86,共8页
“行刑”衔接是我国建设法治政府、法治社会的迫切要求,也是促进依法行政和公正司法的重要举措。2023年7月,最高人民检察院专门印发关于行刑双向衔接的意见,“行刑”衔接的外延明确包括“正向衔接”和“反向衔接”。实践中,“行刑”反... “行刑”衔接是我国建设法治政府、法治社会的迫切要求,也是促进依法行政和公正司法的重要举措。2023年7月,最高人民检察院专门印发关于行刑双向衔接的意见,“行刑”衔接的外延明确包括“正向衔接”和“反向衔接”。实践中,“行刑”反向衔接存在不刑不罚、应移未移、应罚未罚等问题,因此,有必要分析当前“行刑”反向衔接的实践难点及原因,进而在制度设计、平台建设、标准流程、统筹协调等方面,完善“行刑”反向衔接机制。 展开更多
关键词 “行刑”反向衔接 不起诉 实践难点 优化完善
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韶文化融入高校思想政治教育的现实意义和实现路径
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作者 张萌 李燕燕 《深圳信息职业技术学院学报》 2024年第2期22-28,共7页
韶文化作为中华优秀传统文化,具有“源、流、交、融”的内涵,包括红色文化、韶乐文化、家风文化、名人文化、工矿文化等文化内容,其精神特质为包容和谐、耕读传家、尽善尽美。韶文化融入高校思想政治教育对于韶文化、高校思想政治教育... 韶文化作为中华优秀传统文化,具有“源、流、交、融”的内涵,包括红色文化、韶乐文化、家风文化、名人文化、工矿文化等文化内容,其精神特质为包容和谐、耕读传家、尽善尽美。韶文化融入高校思想政治教育对于韶文化、高校思想政治教育、大学生的发展均有现实意义,可以通过建设韶文化校园网站、挖掘韶文化教学资源、拓宽韶文化教学阵地,同时利用现代科技丰富教学,高校、政府、媒体合力育人的具体路径来实现韶文化融入高校思想政治教育。 展开更多
关键词 韶文化 思想政治教育 尽善尽美
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唐君毅的和合思维
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作者 蔡家和 Jason T.Clower(译) 《孔学堂》 CSSCI 2024年第1期1-13,110-122,共26页
唐君毅先生学识渊博,对于中、西、印学皆有一定程度的研究。而他的个性圆融,在面对历史上各家或学派论争时,大多不会去评判各派的高低或对错,而是看出各家专长所在,各给出一个位子。此近似郭象之圆教观,所谓的各美其美!唐先生此一和合... 唐君毅先生学识渊博,对于中、西、印学皆有一定程度的研究。而他的个性圆融,在面对历史上各家或学派论争时,大多不会去评判各派的高低或对错,而是看出各家专长所在,各给出一个位子。此近似郭象之圆教观,所谓的各美其美!唐先生此一和合态度与圆融思想,除了是他个性使然,亦与他涵泳于中华文化而深得其味有关,诸如华严宗的一多相即、相摄相入;《庄子·天下篇》道术之六通四辟、无乎不在,以及《中庸》的中和思想、万物并育而不相害等精神,在滋养其非凡卓识与感通精神——其卓识要去创辟天地之包容,其感通要去持应万物之共谐,从而圆成唐先生心中华夏文化之谐和天地。 展开更多
关键词 和合 圆融 分别 唐君毅 相摄相入
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