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Electron correlation in two-electron atoms:A Bohmian analysis of high-order harmonic generation in high-frequency domain 被引量:1
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作者 Yang Song Shu Han +1 位作者 Yujun Yang Fuming Guo 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第12期249-257,共9页
In studying interactions between intense laser fields and atoms or molecules,the role of electron correlation effects on the dynamical response is an important and pressing issue to address.Utilizing Bohmian mechanics... In studying interactions between intense laser fields and atoms or molecules,the role of electron correlation effects on the dynamical response is an important and pressing issue to address.Utilizing Bohmian mechanics(BM),we have theoretically explored the two-electron correlation characteristics while generating high-order harmonics in xenon atoms subjected to intense laser fields.We initially employed Bohmian trajectories to reproduce the dynamics of the electrons and subsequently utilized time-frequency analysis spectra to ascertain the emission time windows for high-order harmonics.Within these time windows,we classified the nuclear region Bohmian trajectories and observed that intense high-order harmonics are solely generated when paired Bohmian particles(BPs)concurrently appear in the nuclear region and reside there for a duration within a re-collision time window.Furthermore,our analysis of characteristic trajectories producing high-order harmonics led us to propose a two-electron re-collision model to elucidate this phenomenon.The study demonstrates that intense high-order harmonics are only generated when both electrons are in the ground state within the re-collision time window.This work discusses the implications of correlation effects between two electrons and offers valuable insights for studying correlation in multi-electron high-order harmonic generation. 展开更多
关键词 Bohmian mechanics high-order harmonics generation two-electron atom
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Effect of electron correlation on high-order harmonic generation in helium model atom
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作者 胡师林 史庭云 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期171-174,共4页
High-order harmonic generation (HHG) of a helium model atom in an intense laser field has been numerically investigated. The influence of electron correlation on HHG is analysed by changing the strength between the ... High-order harmonic generation (HHG) of a helium model atom in an intense laser field has been numerically investigated. The influence of electron correlation on HHG is analysed by changing the strength between the electrons. The numerical results show that as the electron interaction strength becomes small, the first ionization energy increases rapidly, which results in the decrease in ionization. So the conversion efficiency of the high harmonic lying in the plateau decreases greatly, while the cutoff harmonic order in the harmonic spectrum increases. 展开更多
关键词 electron correlation high-order harmonic generation B-SPLINE
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Labor Relations数据集构造决策树的新方法
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作者 黄俊南 《保山学院学报》 2025年第2期60-70,共11页
采用新型多变量决策树算法对Labor Relations数据集构建决策树,成功获取完整决策表达式。算法在执行原始数据时表现准确无误,能有效处理多达16个条件属性的数据集。同时,证明算法在独立决策条件依赖关系的判定有效,也发现约简法则存在... 采用新型多变量决策树算法对Labor Relations数据集构建决策树,成功获取完整决策表达式。算法在执行原始数据时表现准确无误,能有效处理多达16个条件属性的数据集。同时,证明算法在独立决策条件依赖关系的判定有效,也发现约简法则存在改进潜力。该算法构建决策逻辑过程易于理解且复杂度低,能很好地实现劳资关系样本数据的快速鉴别。 展开更多
关键词 人工智能 劳务关系 多变量决策树 集合运算 逻辑运算
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Chinese satellite frequency and orbit entity relation extraction method based on dynamic integrated learning 被引量:1
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作者 Yuanzhi He Zhiqiang Li Zheng Dou 《Digital Communications and Networks》 2025年第3期787-794,共8页
Given the scarcity of Satellite Frequency and Orbit(SFO)resources,it holds paramount importance to establish a comprehensive knowledge graph of SFO field(SFO-KG)and employ knowledge reasoning technology to automatical... Given the scarcity of Satellite Frequency and Orbit(SFO)resources,it holds paramount importance to establish a comprehensive knowledge graph of SFO field(SFO-KG)and employ knowledge reasoning technology to automatically mine available SFO resources.An essential aspect of constructing SFO-KG is the extraction of Chinese entity relations.Unfortunately,there is currently no publicly available Chinese SFO entity Relation Extraction(RE)dataset.Moreover,publicly available SFO text data contain numerous NA(representing for“No Answer”)relation category sentences that resemble other relation sentences and pose challenges in accurate classification,resulting in low recall and precision for the NA relation category in entity RE.Consequently,this issue adversely affects both the accuracy of constructing the knowledge graph and the efficiency of RE processes.To address these challenges,this paper proposes a method for extracting Chinese SFO text entity relations based on dynamic integrated learning.This method includes the construction of a manually annotated Chinese SFO entity RE dataset and a classifier combining features of SFO resource data.The proposed approach combines integrated learning and pre-training models,specifically utilizing Bidirectional Encoder Representation from Transformers(BERT).In addition,it incorporates one-class classification,attention mechanisms,and dynamic feedback mechanisms to improve the performance of the RE model.Experimental results show that the proposed method outperforms the traditional methods in terms of F1 value when extracting entity relations from both balanced and long-tailed datasets. 展开更多
关键词 Knowledge graph relation extraction One-class classification Satellite frequency and orbit resources BERT
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Link-16 anti-jamming performance evaluation based on grey relational analysis and cloud model 被引量:1
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作者 NING Xiaoyan WANG Ying +1 位作者 WANG Zhenduo SUN Zhiguo 《Journal of Systems Engineering and Electronics》 2025年第1期62-72,共11页
Anti-jamming performance evaluation has recently received significant attention. For Link-16, the anti-jamming performance evaluation and selection of the optimal anti-jamming technologies are urgent problems to be so... Anti-jamming performance evaluation has recently received significant attention. For Link-16, the anti-jamming performance evaluation and selection of the optimal anti-jamming technologies are urgent problems to be solved. A comprehensive evaluation method is proposed, which combines grey relational analysis (GRA) and cloud model, to evaluate the anti-jamming performances of Link-16. Firstly, on the basis of establishing the anti-jamming performance evaluation indicator system of Link-16, the linear combination of analytic hierarchy process(AHP) and entropy weight method (EWM) are used to calculate the combined weight. Secondly, the qualitative and quantitative concept transformation model, i.e., the cloud model, is introduced to evaluate the anti-jamming abilities of Link-16 under each jamming scheme. In addition, GRA calculates the correlation degree between evaluation indicators and the anti-jamming performance of Link-16, and assesses the best anti-jamming technology. Finally, simulation results prove that the proposed evaluation model can achieve the objective of feasible and practical evaluation, which opens up a novel way for the research of anti-jamming performance evaluations of Link-16. 展开更多
关键词 LINK-16 ANTI-JAMMING grey relational analysis(GRA) cloud model combination weights
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Multi-View Picture Fuzzy Clustering:A Novel Method for Partitioning Multi-View Relational Data 被引量:1
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作者 Pham Huy Thong Hoang Thi Canh +2 位作者 Luong Thi Hong Lan Nguyen Tuan Huy Nguyen Long Giang 《Computers, Materials & Continua》 2025年第6期5461-5485,共25页
Multi-view clustering is a critical research area in computer science aimed at effectively extracting meaningful patterns from complex,high-dimensional data that single-view methods cannot capture.Traditional fuzzy cl... Multi-view clustering is a critical research area in computer science aimed at effectively extracting meaningful patterns from complex,high-dimensional data that single-view methods cannot capture.Traditional fuzzy clustering techniques,such as Fuzzy C-Means(FCM),face significant challenges in handling uncertainty and the dependencies between different views.To overcome these limitations,we introduce a new multi-view fuzzy clustering approach that integrates picture fuzzy sets with a dual-anchor graph method for multi-view data,aiming to enhance clustering accuracy and robustness,termed Multi-view Picture Fuzzy Clustering(MPFC).In particular,the picture fuzzy set theory extends the capability to represent uncertainty by modeling three membership levels:membership degrees,neutral degrees,and refusal degrees.This allows for a more flexible representation of uncertain and conflicting data than traditional fuzzy models.Meanwhile,dual-anchor graphs exploit the similarity relationships between data points and integrate information across views.This combination improves stability,scalability,and robustness when handling noisy and heterogeneous data.Experimental results on several benchmark datasets demonstrate significant improvements in clustering accuracy and efficiency,outperforming traditional methods.Specifically,the MPFC algorithm demonstrates outstanding clustering performance on a variety of datasets,attaining a Purity(PUR)score of 0.6440 and an Accuracy(ACC)score of 0.6213 for the 3 Sources dataset,underscoring its robustness and efficiency.The proposed approach significantly contributes to fields such as pattern recognition,multi-view relational data analysis,and large-scale clustering problems.Future work will focus on extending the method for semi-supervised multi-view clustering,aiming to enhance adaptability,scalability,and performance in real-world applications. 展开更多
关键词 Multi-view clustering picture fuzzy sets dual anchor graph fuzzy clustering multi-view relational data
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New Features and New Challenges of U.S.-Europe Relations Under Trump 2.0 被引量:1
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作者 Zhao Huaipu 《Contemporary World》 2025年第3期47-52,共6页
During Donald Trump’s first term,the“Trump Shock”brought world politics into an era of uncertainties and pulled the transatlantic alliance down to its lowest point in history.The Trump 2.0 tsunami brewed by the 202... During Donald Trump’s first term,the“Trump Shock”brought world politics into an era of uncertainties and pulled the transatlantic alliance down to its lowest point in history.The Trump 2.0 tsunami brewed by the 2024 presidential election of the United States has plunged the U.S.-Europe relations into more gloomy waters,ushering in a more complex and turbulent period of adjustment. 展开更多
关键词 new features turbulent period Trump U S Europe relations presidential election new challenges UNCERTAINTIES transatlantic alliance
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A close look at few-shot real image super-resolution from the distortion relation perspective
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作者 Xin Li Xin Jin +3 位作者 Jun Fu Xiaoyuan Yu Bei Tong Zhibo Chen 《中国科学技术大学学报》 北大核心 2025年第7期2-13,1,I0001,共14页
Collecting amounts of distorted/clean image pairs in the real world is non-trivial,which severely limits the practical application of these supervised learning-based methods to real-world image super-resolution(RealSR... Collecting amounts of distorted/clean image pairs in the real world is non-trivial,which severely limits the practical application of these supervised learning-based methods to real-world image super-resolution(RealSR).Previous works usually address this problem by leveraging unsupervised learning-based technologies to alleviate the dependency on paired training samples.However,these methods typically suffer from unsatisfactory texture synthesis due to the lack of supervision of clean images.To overcome this problem,we are the first to take a close look at the under-explored direction for RealSR,i.e.,few-shot real-world image super-resolution,which aims to tackle the challenging RealSR problem with few-shot distorted/clean image pairs.Under this brand-new scenario,we propose distortion relation guided transfer learning(DRTL)for the few-shot RealSR by transferring the rich restoration knowledge from auxiliary distortions(i.e.,synthetic distortions)to the target RealSR under the guidance of the distortion relation.Concretely,DRTL builds a knowledge graph to capture the distortion relation between auxiliary distortions and target distortion(i.e.,real distortions in RealSR).Based on the distortion relation,DRTL adopts a gradient reweighting strategy to guide the knowledge transfer process between auxiliary distortions and target distortions.In this way,DRTL is able to quickly learn the most relevant knowledge from the synthetic distortions for the target distortion.We instantiate DRTL with two commonly-used transfer learning paradigms,including pretraining and meta-learning pipelines,to realize a distortion relation-aware few-shot RealSR.Extensive experiments on multiple benchmarks and thorough ablation studies demonstrate the effectiveness of our DRTL. 展开更多
关键词 few-shot RealSR distortion relation graph transfer learning
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Congratulatory Message by H.E.Mr.Chatchai Viriyavejakul,Ambassador of the Kingdom of Thailand to the People’s Republic of China On the Occasion of the 50th Anniversary of the Establishment of Thailand-China Diplomatic Relations
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《China Report ASEAN》 2025年第6期23-23,共1页
I am delighted to join my Thai and Chinese friends in celebrating the 50th anniversary of the establishment of diplomatic relations between our two great nations.It is the“Golden Jubilee”of Thailand-China friendship... I am delighted to join my Thai and Chinese friends in celebrating the 50th anniversary of the establishment of diplomatic relations between our two great nations.It is the“Golden Jubilee”of Thailand-China friendship.Half a century ago when Thailand’s then Prime Minister M.R.Kukrit Pramoj and China’s Premier Zhou Enlai signed a Joint Communique on the Establishment of Diplomatic Relations on July 1,1975,the foundation for a profound and mutually beneficial partnership was laid,fostering enduring friendship,cooperation,and understanding between our two nations.This bond has stood the test of time amidst the ever-changing international landscape and been further enhanced by both countries’commitment to advancing the Comprehensive Strategic Cooperative Partnership and building a Thailand-China community with a shared future for enhanced stability,prosperity,and sustainability through a forwardlooking and people-centered vision. 展开更多
关键词 shared future Thailand China relations diplomatic relations comprehensive strategic cooperative partnership establishment diplomatic relations golden jubilee
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A Review of Joint Extraction Techniques for Relational Triples Based on NYT and WebNLG Datasets
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作者 Chenglong Mi Huaibin Qin +1 位作者 Quan Qi Pengxiang Zuo 《Computers, Materials & Continua》 2025年第3期3773-3796,共24页
In recent years,with the rapid development of deep learning technology,relational triplet extraction techniques have also achieved groundbreaking progress.Traditional pipeline models have certain limitations due to er... In recent years,with the rapid development of deep learning technology,relational triplet extraction techniques have also achieved groundbreaking progress.Traditional pipeline models have certain limitations due to error propagation.To overcome the limitations of traditional pipeline models,recent research has focused on jointly modeling the two key subtasks-named entity recognition and relation extraction-within a unified framework.To support future research,this paper provides a comprehensive review of recently published studies in the field of relational triplet extraction.The review examines commonly used public datasets for relational triplet extraction techniques and systematically reviews current mainstream joint extraction methods,including joint decoding methods and parameter sharing methods,with joint decoding methods further divided into table filling,tagging,and sequence-to-sequence approaches.In addition,this paper also conducts small-scale replication experiments on models that have performed well in recent years for each method to verify the reproducibility of the code and to compare the performance of different models under uniform conditions.Each method has its own advantages in terms of model design,task handling,and application scenarios,but also faces challenges such as processing complex sentence structures,cross-sentence relation extraction,and adaptability in low-resource environments.Finally,this paper systematically summarizes each method and discusses the future development prospects of joint extraction of relational triples. 展开更多
关键词 relation triplet extraction joint extraction methods named entity recognition relation extraction
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REVITALIZING TIES FOR A SHARED FUTURE China and the Philippines need to work together to bring bilateral relations back to a track of healthy and stable development
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作者 Ye Jingtong Ma Yuchen 《China Report ASEAN》 2025年第6期56-59,共4页
The year 2025 marks the 50th anniversary of diplomatic relations between China and the Philippines.Over the past half century,despite ups and downs,China-Philippines relations have maintained a steady momentum of deve... The year 2025 marks the 50th anniversary of diplomatic relations between China and the Philippines.Over the past half century,despite ups and downs,China-Philippines relations have maintained a steady momentum of development with continuous progress in political,economic,and cultural exchanges.Since the second half of 2023,the Philippines’freguent provocations in the South China Sea have negatively impacted bilateral relations. 展开更多
关键词 shared future diplomatic relations bilateral relations China political exchanges Philippines South China Sea economic exchanges
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WEAPONIZING TRADE, UNDERMINING TRUST The Trump administration’s politicization of global economics threatens international stability and damages China-U.S. relations
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作者 Hamzah Rifaat Hussain 《China Report ASEAN》 2025年第5期64-64,共1页
If there were any doubts about the Trump administration’s inherent obsession with decoupling,polarization and jolting of global trade,they can be laid to rest.A series of statements and measures have been made by the... If there were any doubts about the Trump administration’s inherent obsession with decoupling,polarization and jolting of global trade,they can be laid to rest.A series of statements and measures have been made by the U.S.government on economic relations with China including administrative decision to hit Chinese goods with additional tariffs despite China. 展开更多
关键词 global trade economic relations trade decoupling international stability tariffs polarization TRUST china u s relations
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Frequency shifts of high-order harmonics from ZnO crystals by chirped laser pulses
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作者 Yu Zhao Xiao-Jin Liu +3 位作者 Shuang Wang Xiao-Xin Huo Yun-He Xing Jun Zhang 《Chinese Physics B》 2025年第3期340-346,共7页
We investigate theoretically the effects of chirped laser pulses on high-order harmonic generation(HHG)from solids.We find that the harmonic spectra display redshifts for the driving laser pulses with negative chirp a... We investigate theoretically the effects of chirped laser pulses on high-order harmonic generation(HHG)from solids.We find that the harmonic spectra display redshifts for the driving laser pulses with negative chirp and blueshifts for those with positive chirp,which is due to the change in the instantaneous frequency of the driving laser for different chirped pulses.The analysis of crystal-momentum-resolved(k-resolved)HHG reveals that the frequency shifts are equal for the harmonics generated by different crystal momentum channels.The frequency shifts in the cutoff region are larger than those in the plateau region.With the increase of the absolute value of the chirp parameters,the frequency shifts of HHG become more significant,leading to the shifts from odd-to even-order harmonics.We also demonstrate that the frequency shifts of harmonic spectra are related to the duration of the chirped laser field,but are insensitive to the laser intensity and dephasing time. 展开更多
关键词 high-order harmonic generation ZnO crystal chirped laser pulse spectral shift
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Accessing polyarene-fused ten-membered lactams via oxidative N-heterocyclic carbene(NHC)-catalyzed high-order[7+3]annulation
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作者 Chen-Chang Cui Shao-Qing Shi +4 位作者 Lu-Yao Wang Feng Lin Man-Su Tu Wen-Juan Hao Bo Jiang 《Chinese Chemical Letters》 2025年第6期479-483,共5页
A new oxidative N-heterocyclic carbene(NHC)-catalyzed high-order[7+3]annulation reaction ofγ-indolyl phenols as 1,7-dinucleophiles andα,β-alkynals with the aid of Sc(OTf)_(3)is reported,enabling the highly regiosel... A new oxidative N-heterocyclic carbene(NHC)-catalyzed high-order[7+3]annulation reaction ofγ-indolyl phenols as 1,7-dinucleophiles andα,β-alkynals with the aid of Sc(OTf)_(3)is reported,enabling the highly regioselective access to unprecedented polyarene-fused ten-membered lactams bearing a bridged aryl-aryl-indole scaffold in moderate to good yields.This protocol demonstrates a broad substrate scope,good compatibility with substituents and complete regioselectivity,providing an organocatalytic modular synthetic strategy for creating medium-sized lactams. 展开更多
关键词 NHC-catalysis high-order annulation Regioselectivity Medium-sized lactams γ-Indolyl phenols
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Unveiling the role of high-order anharmonicity in thermal expansion: A first-principles perspective
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作者 Tianxu Zhang Kun Zhou +5 位作者 Yingjian Li Chenhao Yi Muhammad Faizan Yuhao Fu Xinjiang Wang Lijun Zhang 《Chinese Physics B》 2025年第4期212-219,共8页
Thermal expansion is crucial for various industrial processes and is increasingly the focus of research endeavors aimed at improving material performance.However,it is the continuous advancements in first-principles c... Thermal expansion is crucial for various industrial processes and is increasingly the focus of research endeavors aimed at improving material performance.However,it is the continuous advancements in first-principles calculations that have enabled researchers to understand the microscopic origins of thermal expansion.In this study,we propose a coefficient of thermal expansion(CTE)calculation scheme based on self-consistent phonon theory,incorporating the fourth-order anharmonicity.We selected four structures(Si,CaZrF_(6),SrTiO_(3),NaBr)to investigate high-order anharmonicity’s impact on their CTEs,based on bonding types.The results indicate that our method goes beyond the second-order quasi-harmonic approximation and the third-order perturbation theory,aligning closely with experimental data.Furthermore,we observed that an increase in the ionicity of the structures leads to a more pronounced influence of high-order anharmonicity on CTE,with this effect primarily manifesting in variations of the Grüneisen parameter.Our research provides a theoretical foundation for accurately predicting and regulating the thermal expansion behavior of materials. 展开更多
关键词 high-order anharmonicity Grüneisen parameter thermal expansion first-principles calculations
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Stronger Ties and a Shared Future Indonesian Ambassador Djauhari Oratmangun reflects on 75 years of Indonesia-China relations and prospects for deeper collaboration
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作者 Huang Jiangqin 《China Report ASEAN》 2025年第4期22-23,共2页
The year 2025 marks the 75th anniversary of the establishment of diplomatic relations between China and Indonesia.Over the past 75 years,the bilateral relationship has made significant progress across various fields,l... The year 2025 marks the 75th anniversary of the establishment of diplomatic relations between China and Indonesia.Over the past 75 years,the bilateral relationship has made significant progress across various fields,laying a solid foundation for regional stability.China Report ASEAN interviewed Indonesian Ambassador to China Djauhari Oratmangun to reflect on the remarkable journey of Indonesia-China relations over the past 75 years. 展开更多
关键词 Indonesia China relations regional stability djauhari oratmangun diplomatic relations th anniversary bilateral relationship shared future
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A High-Order Scalar Auxiliary Variable Approach for Nonlinear Parabolic Integro-Differential Equations
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作者 YAN Li-na ZHANG Gen-gen HUANG Qiong-ao 《Chinese Quarterly Journal of Mathematics》 2025年第3期262-270,共9页
An efficient and accurate scalar auxiliary variable(SAV)scheme for numerically solving nonlinear parabolic integro-differential equation(PIDE)is developed in this paper.The original equation is first transformed into ... An efficient and accurate scalar auxiliary variable(SAV)scheme for numerically solving nonlinear parabolic integro-differential equation(PIDE)is developed in this paper.The original equation is first transformed into an equivalent system,and the k-order backward differentiation formula(BDF k)and central difference formula are used to discretize the temporal and spatial derivatives,respectively.Different from the traditional discrete method that adopts full implicit or full explicit for the nonlinear integral terms,the proposed scheme is based on the SAV idea and can be treated semi-implicitly,taking into account both accuracy and effectiveness.Numerical results are presented to demonstrate the high-order convergence(up to fourth-order)of the developed schemes and it is computationally efficient in long-time computations. 展开更多
关键词 Parabolic integro-differential equation Scalar auxiliary variable Fredholm equation high-order BDF scheme
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An Evaluation and Similarity Analysis of Provincial Green Development Levels in China Using Grey Relational Analysis
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作者 Fan Bo Chen Qian 《Contemporary Social Sciences》 2025年第1期47-68,共22页
Green development is vital for bringing about high-quality development,which makes measuring and comparing provincial green development levels essential.This study calculates the comprehensive green development scores... Green development is vital for bringing about high-quality development,which makes measuring and comparing provincial green development levels essential.This study calculates the comprehensive green development scores using panel data from 30 Chinese provinces and autonomous regions(2013-2022)and a combined subjective-objective weighting method.It also innovatively establishes a grey relational degree matrix and a grey improvement sequence to analyze provincial similarities and identify benchmarks for improvement.The results indicate that ecological and environmental protection holds the highest weight among the primary indicators.Beijing,Shanghai,Tianjin,Zhejiang,and Jiangsu lead in green development,with Shanghai,Beijing,and Tianjin exhibiting distinct development trajectories,while Guizhou and Yunnan share a similar trend.Zhejiang and Shaanxi have prominent benchmarks for improvement,while some provinces dynamically adjust their targets.The results suggest that advanced regions should further refine their green development pathways to align with their specific contexts,while less-developed regions should adaptively learn from the appropriate benchmarks and periodically reassess their strategies.This study provides scientific guidance for regional green development planning,policymaking,and benchmarking,thus contributing to sustainable regional development.Furthermore,it lays a foundation for future research to expand into broader datasets,scales,influencing factors,and policy evaluations. 展开更多
关键词 green development grey relational degree grey relational degree matrix grey improvement sequence benchmark for improvement
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China-EU Cooperation Could Not Have Been Better Timed--On the Occasion of the 50th Anniversary of China-EU Diplomatic Relations
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作者 《Contemporary World》 2025年第4期22-27,共6页
This year marks the 50th anniversary of the establishment of diplomatic relations between China and the EU.Over half a century,China and the EU have steadily enhanced political mutual trust,deepened mutually beneficia... This year marks the 50th anniversary of the establishment of diplomatic relations between China and the EU.Over half a century,China and the EU have steadily enhanced political mutual trust,deepened mutually beneficial cooperation,and firmly upheld multilateralism,bringing tangible benefits to both peoples and making a significant contribution to global peace and development. 展开更多
关键词 EU Mutually Beneficial Cooperation Political Mutual Trust China Diplomatic relations enhanced political mutual trustdeepened establishment diplomatic relations MULTILATERALISM
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Influence of excited states in high-order harmonic generation at intense mid-infrared field
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作者 Yan Fang Da-Wei Tian +2 位作者 Yue Cao Xiao-Lei Hao Zheng Shu 《Chinese Physics B》 2025年第10期142-147,共6页
We present a comprehensive study on the role of various excited states in high-order harmonic generation of hydrogen atoms driven by a long-wavelength(1500 nm)laser field.By numerically solving the time-dependent Schr... We present a comprehensive study on the role of various excited states in high-order harmonic generation of hydrogen atoms driven by a long-wavelength(1500 nm)laser field.By numerically solving the time-dependent Schrodinger equation(TDSE)and performing a time-frequency analysis,we investigate the influence of individual excited states on the harmonic spectrum.Our results reveal that the 2s excited state primarily contributes to the enhancement of high-energy harmonic yields by facilitating long electron trajectories,while the 2p excited state predominantly suppresses harmonic yields in the lower-energy region(20th-50th orders)by altering the contributions of electron trajectories.Our results highlight the critical role of the excited states in the HHG process,even at longer laser wavelengths. 展开更多
关键词 high-order harmonic generation(HHG) strong-field physics excited-state effect
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