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Identity and Reality: Synchronicity of the Grand Canal Culture and Huai'an Historical and Cultural Space
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作者 Xinting LU Shuyuan LV 《Meteorological and Environmental Research》 2025年第1期70-75,共6页
In order to further explore the rich connotation of Huai'an historical and cultural space and the Grand Canal culture,the synchronicity of urban spatial pattern and historical buildings of Huai'an was studied ... In order to further explore the rich connotation of Huai'an historical and cultural space and the Grand Canal culture,the synchronicity of urban spatial pattern and historical buildings of Huai'an was studied under the guidance of synchronic theory and method.It is found that there are the identity and reality law of the development and change of Huai'an historical and cultural space and the Grand Canal cultural system,and it is deduced that there is a spiraling systematic structure chain between the historical and cultural space of Huai'an and the Grand Canal culture,which provides a theoretical reference for promoting the deepening construction of regional culture,the Grand Canal cultural belt and national cultural parks. 展开更多
关键词 Grand Canal culture Historical and cultural space Historic buildings synchronicITY
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The synchronicity and difference in the change of suspended sediment concentration in the Yangtze River Estuary 被引量:8
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作者 YANG Yunping DENG Jinyun +2 位作者 ZHANG Mingjin LI Yitian LIU Wanli 《Journal of Geographical Sciences》 SCIE CSCD 2015年第4期399-416,共18页
The sediment discharge from the Yangtze River Basin has a stepwise decreasing trend in recent years. The impounding of the Three Gorges Reservoir exacerbated this de- creasing trend and affected the change of the susp... The sediment discharge from the Yangtze River Basin has a stepwise decreasing trend in recent years. The impounding of the Three Gorges Reservoir exacerbated this de- creasing trend and affected the change of the suspended sediment concentration (SSC) in the Yangtze River Estuary through the transmission effect. The SSC data of the Yangtze River Estuary during 1959-2012 showed that: (1) The SSC in the South Branch of the Yang- tze River in the estuary and in the off-shore sea area displayed decreasing trends and de- creased less towards the sea. At the same time, the difference in decreasing magnitude be- tween SSC and sediment discharge became bigger towards the sea. (2) For the North Branch the preferential flow did not change much but the SSC tended to decrease, which was mainly caused by the decrease of SSC in the South Branch and China East Sea. (3) Due to the de- creased runoff and the relatively strengthened tide, the peak area of the SSC in the bar shoal section in 2003-2012 moved inward for about 1/6 longitude unit compared with that in 1984-2002, and the inward-moving distance was in the order of flood season 〉 annual average 〉 dry season. (4) In the inlet of the South Passage, the SSC decreased mainly because the increase caused by resuspension and shore-groove exchange was less than the decrease caused by the sharp SSC decrease in the basin and the sea areas. The reverse was true in the middle section, where the SSC showed an increasing trend. (5) In the inlet of the North Passage, under the combined influence of decreased flow split and sediment split ratios, the decreased SSC in the basin and the sea area and decreased amount of resuspension, the SSC displayed a decreasing trend. In the middle section, because the increased amount caused by sediment going over the dyke was markedly more than the decreased amount caused by external environments, the SSC tended to increase. Holistically, the sharp decrease in sediment discharge caused synchronized SSC decreases in the Yangtze River Estuary. But there were still areas, where the SSC displayed increasing trends, indicatingsynchronicity and difference in the response of SSC to the sharp decrease in sediment discharge from the basin. 展开更多
关键词 suspended sediment concentration synchronicITY DIFFERENCE sediment discharge Yangtze River Es-tuary
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The Usage of “xiaojie (小姐)” in Contem porary Chinese: Synchronic Differences in Distribution and Possibilities for Diachronic Change 被引量:1
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作者 Hu Fanzhu Fan Xiaoling 《宏观语言学》 2007年第1期130-140,共11页
xiaojie(小姐, miss) is a popular form of address in contemporary Chinese; generally speaking, it is defined as a title for ―unmarried girl. This form has multiple connotations,. Given recent changes in society, some... xiaojie(小姐, miss) is a popular form of address in contemporary Chinese; generally speaking, it is defined as a title for ―unmarried girl. This form has multiple connotations,. Given recent changes in society, some think that, xiaojie (小姐) will become a widely-used form of address, while others think that young females will come to consider the title repulsive. None can have the final say, this is because the synchronic language differences are not only the result of the synchronic change but also possibly its sign. Since synchronic differences could not only be a result of diachronic change but also could herald further change, it is not clear what direction xiaojie (小姐) will take. In the language conflicts, When two language varieties conflict, the more common variety usually influences the less common. A field investigation in large cities throughout China thus allows us not only to draw A Distributional Map of Pragmatic Features of the Title xiaojie(小姐) ,but also enables us to see its diachronic possibilities. 展开更多
关键词 address XIAOJIE PRAGMATICS synchronic DISTRIBUTION DIACHRONIC CHANGE
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Local records of long-term dynamics of bamboo gregarious flowering in northern Laos and regional synchronicity of Dendrocalamus membranaceus in two flowering sites 被引量:2
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作者 HIROTA Isao 《Journal of Mountain Science》 SCIE CSCD 2017年第6期1058-1064,共7页
Bamboos are widely distributed in mainland Southeast Asia and have abundant biomass. They are characterized by prolonged vegetative growth and semelparity. Where bamboos are dominant, their synchronous flowering and d... Bamboos are widely distributed in mainland Southeast Asia and have abundant biomass. They are characterized by prolonged vegetative growth and semelparity. Where bamboos are dominant, their synchronous flowering and death has a major impact on forest vegetation. Although the small-scale dynamics of this process have become clearer in recent years, the history, geographical scale and synchronicity of bamboo flowering over broad areas remains unknown. This study focused on the flowering history of six bamboo species, Bambusa tulda, Cephalostachyum virgatum, Dendrocalamus hamiltonii, Dendrocalamus membranaceus, Indosasa sinica and Oxytenanthera parvifolia, over 40 years across a broad area of northern Laos. We also examined the synchronicity of flowering in D. membranaceus. We visited 49 villages in northern Laos and surveyed knowledgeable inhabitants about bamboo flowering history. The timing, scale and synchronicity of gregarious flowering varied among species. D. hamiltonii and D. membranaceus showed higher flowering synchronicity than other species. All the species except I. sinica had both sporadic and gregarious flowering traits, and showed conspicuous variability in their flowering scale. The flowering bamboo population at two gregarious flowering sites for D. membranaceus was surveyed. While thisspecies had the highest synchronicity in this study, its synchronicity was lower than other species in previous studies worldwide. We found that the gregarious flowering of bamboos in northern Laos over the last 40 years showed lower synchronicity than bamboo flowering reported in other areas of the world. The historical dynamics and scale of bamboo flowering must be further clarified to understand the vegetation composition of this area. 展开更多
关键词 Fallow forest Sporadic flowering Shifting cultivation synchronicity Southeast Asia
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Compensation:A Synchronic Dynamic Mechanism in Language
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作者 Ma Qinghua Wang Zhiguang 《宏观语言学》 2008年第1期14-37,共24页
In this paper, compensation mechanism—a synchronic dynamic rule in language is postulated and theorized. The rule raises the acceptability of clauses by effecting the positive side of some variations with exceptional... In this paper, compensation mechanism—a synchronic dynamic rule in language is postulated and theorized. The rule raises the acceptability of clauses by effecting the positive side of some variations with exceptional expression and offsetting their negative side. This mechanism is determined by the instrumentality and systematicality of language so that its basic principle should be applicable to all exceptional expressions for particular positive effects and thus universal synchronically. 展开更多
关键词 COMPENSATION synchronic DYNAMIC MECHANISM ACCEPTABILITY
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Fibonacci Harmonics: A New Mathematical Model of Synchronicity
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作者 Robert G. Sacco 《Applied Mathematics》 2018年第6期702-718,共17页
This article aims to provide a brief overview of the relevance of new findings about the Fibonacci Life Chart Method (FLCM) for understanding synchronicity. The FLCM is reviewed first, including an exposition of the g... This article aims to provide a brief overview of the relevance of new findings about the Fibonacci Life Chart Method (FLCM) for understanding synchronicity. The FLCM is reviewed first, including an exposition of the golden section model, and elaboration of a new harmonic model. The two models are then compared to illuminate several strengths and weaknesses in connection with the following four major criteria regarding synchronicity: explanatory adequacy;predictability of future synchronicities;simplicity of the model;and generalizability to other branches of knowledge. The review indicates that both models appear capable of simulating nonlinear and fractal dynamics. Hybrid approaches that combine both models are feasible and necessary for projects that aim to experimentally address synchronicity. 展开更多
关键词 synchronicITY Dynamical Systems Brain Dynamics FIBONACCI Life CHART Method GOLDEN Section MODEL Harmonic MODEL
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Do Planetary Transits Predict Synchronicity Experience?
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作者 Robert G. Sacco 《Journal of Behavioral and Brain Science》 CAS 2023年第3期33-44,共12页
Synchronicity involves the experience of personal meaning entangled with ambiguous coincidences in time. Ambiguity results from incomplete information about the chances of various events occurring. The problem that th... Synchronicity involves the experience of personal meaning entangled with ambiguous coincidences in time. Ambiguity results from incomplete information about the chances of various events occurring. The problem that this study addresses is the lack of empirical research on synchronicity. This study sought to address this problem by exploring the astrological hypothesis that planetary transits predict synchronicity events. Synchronicities were compared with the probability distributions of planetary transits. In comparison with the base rate prediction, planetary transits were not a significant predictor of synchronicity events. The findings of this study provide new insight into the complex, multifaceted, and ambiguous phenomenon of synchronicity. The concept of ambiguity tolerance plays a significant role in synchronicity research since ambiguity cannot be completely eliminated. 展开更多
关键词 ASTROLOGY Fibonacci Numbers Planetary Transits synchronicITY
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On the Jefimenko’s Non-Einsteinian Clocks and Synchronicity of Moving Clocks
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作者 Andrew Chubykalo Augusto Espinoza 《Journal of Modern Physics》 2017年第4期439-447,共9页
In this work we analyze the concept of time dilation in its application to the rate of moving clocks. The rates of two equiform elementary electromagnetic clocks of different orientations relative to their direction o... In this work we analyze the concept of time dilation in its application to the rate of moving clocks. The rates of two equiform elementary electromagnetic clocks of different orientations relative to their direction of motion are computed on the basis of relativistic transformations of force and coordinates for the case when the clocks are at rest in a stationary reference frame and for the case when they are moving at constant speed relative to the stationary reference frame. It is shown that, although both clocks run slower when they are moving than when they are at rest, the rate of the moving clocks is affected by their orientation relative to their direction of motion, rather than by the kinematic (relativistic) time dilation as it is now generally assumed. The implication of this result for the experimental proofs of the existence of the kinematic the dilation is discussed. 展开更多
关键词 synchronicITY TIME DILATION LENGTH CONTRACTION
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Pulsed Doppler Tissue Imaging for Assessment of Left Ventricular Systolic and Diastolic Synchronicity in Normal Subjects
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作者 杨莉 伍卫 +1 位作者 王景峰 张小玲 《South China Journal of Cardiology》 CAS 2006年第1期18-21,共4页
Objectives To quantitatively analyze the longitudinal myocardial systolic and diastolic velocities and time intervals of the left ventricle in normal subjects, and to explore the value of pulsed Doppler tissue imaging... Objectives To quantitatively analyze the longitudinal myocardial systolic and diastolic velocities and time intervals of the left ventricle in normal subjects, and to explore the value of pulsed Doppler tissue imaging (DTI) for the assessment of left ventricular systolic and diastolic synchronicity. Methods Twenty and six healthy subjects were studied by pulsed DTI. The septal and lateral, anterior and inferior walls of the left ventricle were displayed respectively, and basal and middle segments of each wall were selected for myocardial motion spectrum sampling. DTI parameters were: peak systolic myocardial velocity (s), regional pre-ejection period (PEP), time to the peak of s wave (Ts), regional ejection time (ET) ; peak early diastolic velocity (e), peak late diastolic velocity (a), e/a ratio, time to the beginning of e wave (QE), time to the peak of e wave (Te) and regional isovolumic relaxation time (IVRT). Results The e and e/a were significantly different among basal segments, and s and e/a were significantly different among middle segments, with the highest value in lateral segments and the lowest value in septal segments. The s, e and a were all significantly higher in basal segments than middle segments. None of the systolic time intervals (PEP, Ts and ET) and diastolic time intervals (QE, Te and IVRT) were significantly different among basal segments and middle segments, neither were they when basal segment was compared with middle segment. Conclusions In normal subjects, the longitudinal myocardial systolic and diastolic velocities of the left ventricle are not homogeneous, but the contraction and relaxation are highly synchronized. Pulsed DTI can be used to quantitatively analyze the systolic and diastolic synchronicity of the heart. 展开更多
关键词 Doppler tissue imaging Echocardiography synchronicity
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Assessment of cardiac function and synchronicity in subjects with isolated bundle branch block using Doppler imaging 被引量:3
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作者 NIU Hong-xia HUA Wei +5 位作者 ZHANG Shu SUN Xin WANG Fang-zheng CHEN Ke-ping WANG Hao CHEN Xin 《Chinese Medical Journal》 SCIE CAS CSCD 2006年第10期795-800,共6页
Background Using tissue Doppler imaging and conventional echocardiographic technique, we examined the cardiac function and synchronicity in individuals with isolated right bundle branch block (RBBB) or left bundle b... Background Using tissue Doppler imaging and conventional echocardiographic technique, we examined the cardiac function and synchronicity in individuals with isolated right bundle branch block (RBBB) or left bundle branch block (LBBB) and assessed the relationship between QRS duration and synchronicity. 展开更多
关键词 bundle branch block synchronicITY cardiac function tissue Doppler imaging
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Ventricular synchronicity: observations comparing pulse flow and tissue Doppler assessment in a Chinese healthy adult cohort 被引量:2
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作者 QUAN Xin ZHU Tian-gang +3 位作者 GUO Shi MA Jian-xin WANG Xin GUO Ji-hong 《Chinese Medical Journal》 SCIE CAS CSCD 2012年第1期27-32,共6页
Background Mechanical asynchrony is an important parameter in predicting the response to cardiac resynchronization therapy, but detailed knowledge about cardiac timing in healthy persons is scarce. Therefore, in the c... Background Mechanical asynchrony is an important parameter in predicting the response to cardiac resynchronization therapy, but detailed knowledge about cardiac timing in healthy persons is scarce. Therefore, in the current study, we sought to investigate the physiological status of interventricular synchronicity using pulse wave flow and tissue Doppler imaging in a healthy Chinese population. Methods Eighty-eight healthy volunteers underwent standard flow and tissue Doppler echocardiographic examinations. Ventricular inflow and outflow pulse wave flow Doppler patterns were recorded together with annulus pulse tissue Doppler imaging. Time intervals from the beginning of the QRS complex to the onset, peak and end of each wave were measured. Results The onsets of systole between left and right ventricles were highly synchronized by both imaging modalities. However, the left ventricle reached the peak flow ejection and peak mechanical contraction earlier than the right ventricle, (165.61±26.23) ms vs. (204.3±34.55) ms (P 〈0.01) and (133.62±26.19) ms vs. (191.25±38.47) ms (P 〈0.01). Time to peak early diastolic relaxation was earlier in the left ventricle than in the right heart, (500.23±56.52) ms vs. (524.94±47.42) ms (P 〈0.01 ). Conclusions Left and right ventricles were well synchronized at the onsets of systole and diastole even though interventricular peak systolic and peak early diastolic dyssynchrony was observed in healthy people by pulse wave Doppler imaging. In addition, diastolic timing events were slightly affected by age and gender. 展开更多
关键词 SYSTOLIC DIASTOLIC DOPPLER synchronicITY
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The capital market spillover effect of product market advertising:Evidence from stock price synchronicity 被引量:3
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作者 Yajie Chen Qinlin Zhong Fuxiu Jiang 《Frontiers of Business Research in China》 2020年第2期196-216,共21页
We analyze whether product market advertising has a spillover effect on stock price synchronicity by transmitting firm-specific information to the capital market and attracting more investor attention.Using a sample o... We analyze whether product market advertising has a spillover effect on stock price synchronicity by transmitting firm-specific information to the capital market and attracting more investor attention.Using a sample of Chinese listed firms from 2009 to 2017,we find that firms with greater advertising expenditures have lower stock price synchronicity.The results are robust after we address endogeneity concerns.In accord with our hypothesis that product market advertising increases the amount of firm-level information capitalized into stock prices through the information channel,we find that the impact of advertising on synchronicity is more pronounced for firms with a higher degree of information asymmetry and firms in the consumer-product industry.Further tests show that product market advertising enhances the ability of current period returns to reflect future earnings,and thus rules out that the negative relationship between advertising and synchronicity is driven by noise trading.Our results imply that product market advertising plays an informative role and improves information efficiency in a capital market. 展开更多
关键词 ADVERTISING Stock price synchronicity Spillover effect Product market Capital market Investor attention Information asymmetry
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Does preventive regulation reduce stock price synchronicity?Evidence from Chinese annual report comment letters 被引量:1
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作者 Xiaomin Hao Yonghai Wang 《China Journal of Accounting Research》 2021年第4期49-73,共25页
Based on a sample of Chinese A-share listed firms from 2015 to 2018,this paper studies the impact of annual report comment letters(ARCLs)on firm stock price synchronicity.We find that after firms receive ARCLs,their s... Based on a sample of Chinese A-share listed firms from 2015 to 2018,this paper studies the impact of annual report comment letters(ARCLs)on firm stock price synchronicity.We find that after firms receive ARCLs,their stock price synchronicity decreases.Moreover,the longer the ARCLs and the more negative the ARCLs’tone,the lower the resulting stock price synchronicity.The mechanism test shows that after firms receive ARCLs,the firms’information disclosure increases in quantity and quality,external media attention increases,and the firms’governance improves,reducing their stock price synchronicity.Further research shows that this negative association is more significant in firms with higher information asymmetry.This paper shows that the ARCL,an innovative application of the capital market supervision philosophy,is conducive to improving the quality of listed firms and to the healthy development of the capital market. 展开更多
关键词 Preventive Regulation Annual Report Comment Letters Stock Price synchronicity Information Asymmetry
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Multi-wavelength pulses in synchronized mode-locked fiber lasers
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作者 WU Qiong GAO Bo +8 位作者 ZHOU Lu-yao WEN Hong-lin QIAO Fei-hong WU Bing XU Ting LI Qi LI Ying-ying WU Ge LIU Lie 《中国光学(中英文)》 北大核心 2026年第2期445-453,共9页
We designed and investigated a passive synchronized mode-locked fiber laser.The device utilizes a dual-cavity structure driven by the nonlinear polarization rotation(NPR)mechanism.Stable mode-locking is attained by sy... We designed and investigated a passive synchronized mode-locked fiber laser.The device utilizes a dual-cavity structure driven by the nonlinear polarization rotation(NPR)mechanism.Stable mode-locking is attained by synergistically controlling gain,polarization state,and optical path length in two symmetric sub-cavities.Experiments proved that repetition rate of the sub-cavities can be adjusted via the time delay line(TDL)to achieve synchronized mode-locking.The system stably generates multi-wavelength pulses at a single repetition frequency,evidenced by multiple spectral peaks and equidistant pulse sequences.These findings facilitate the development of high-performance multi-wavelength ultrashort pulse sources,crucial for optical communications,spectral analysis,and remote sensing. 展开更多
关键词 synchronized mode-locked fiber laser multi-wavelength pulses dual-cavity
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Research on a Digital Virtual Human Lip Synchronization Optimization Algorithm
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作者 FAN Jia-li ZHAO Si-jia SI Zhan-jun 《印刷与数字媒体技术研究》 北大核心 2026年第1期226-235,250,共11页
Lip synchronization serves as a core technology for enabling natural interactions in digital virtual humans.However,it faces challenges such as insufficient dynamic correspondence between speech and lip movements and ... Lip synchronization serves as a core technology for enabling natural interactions in digital virtual humans.However,it faces challenges such as insufficient dynamic correspondence between speech and lip movements and inadequate modeling of image details.To address these limitations,a comprehensively optimized lip synchronization framework extending the Wav2Lip architecture was proposed in this study.Firstly,based on the Wav2Lip model,a facial region extraction strategy using facial keypoints was designed,which effectively enhances the robustness of facial alignment during lip synchronization for digital virtual humans.Then,a cross-modal attention fusion module between visual and speech features was introduced to improve cross-modal information fusion,and a dynamic receptive field convolution module was developed in the generation branch to enhance the modeling performance of the lip region.Finally,experiments were conducted on the VFHQ dataset.The proposed method was compared with Wav2Lip,VideoRetalking,and DI-Net models,and its performance was evaluated using three metrics:LSE-C,CSIM,and FID.Experimental results showed that the proposed method achieves significant improvements in synchronization accuracy and image fidelity,providing an efficient and feasible solution for lip-synthesis tasks of digital virtual humans. 展开更多
关键词 Lip synchronization Digital human Cross-modal attention Audio-visual synthesis
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Synchronizing Semigroups Generated by a Transitive Imprimitive Group and a Transformation
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作者 LI Wangwei LI Xianhua 《数学进展》 北大核心 2026年第2期356-368,共13页
Let T_(n) and S_(n) be the full transformation semigroup and the symmetric group on X_(n)={1,2,...,n},respectively.Let G be a transitiveimprimitive subgroupof S_(n) with nontrivial blocksΔand letαbe a transformation... Let T_(n) and S_(n) be the full transformation semigroup and the symmetric group on X_(n)={1,2,...,n},respectively.Let G be a transitiveimprimitive subgroupof S_(n) with nontrivial blocksΔand letαbe a transformation in T_(n)\S_(n).The kernel ofαis the partition of X_(n) induced by the equivalence relation{(x,y)|xα=yα};the kernel type ofαis the partition of n given by the sizes of the parts of the kernel.A transformation semigroup is called synchronizing if it contains a constant map.Then a group G synchronizes a transformationαif the semigroup(G,α)contains a constant map.In this paper,we study a transitive imprimitive permutation group G together with a non-invertible transformationαthat generate a synchronizing semigroup.We mainly discuss 7 cases where G synchronizes a special transformationαwith each kernel class A_(i)(A_(1)j)satisfying|A_(i)∩Δ|=1(|A_(1)j∩Δ|=1)for all blocksΔofG,that is,the kernel type ofαis(|A_(1)|,1,...,1),(|A_(1)1|,...,|A_(1m)|,|A_(2)|,...,|Ar|),or(|A_(1)|,...,|A_(t)|,1,...,1),or the rank is 2,3,4,or n-2. 展开更多
关键词 transitive imprimitive group completely regular semigroup synchronizing semigroup
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Non-reciprocal Synchronization in Thermal Rydberg Ensembles
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作者 Yunlong Xue Zhengyang Bai 《Chinese Physics Letters》 2026年第1期26-30,共5页
Optical non-reciprocity is a fundamental phenomenon in photonics.It is crucial for developing devices that rely on directional signal control,such as optical isolators and circulators.However,most research in this fie... Optical non-reciprocity is a fundamental phenomenon in photonics.It is crucial for developing devices that rely on directional signal control,such as optical isolators and circulators.However,most research in this field has focused on systems in equilibrium or steady states.In this work,we demonstrate a room-temperature Rydberg atomic platform where the unidirectional propagation of light acts as a switch to mediate time-crystalline-like collective oscillations through atomic synchronization. 展开更多
关键词 atomic synchronization non reciprocal synchronization optical non reciprocity optical isolators thermal Rydberg ensembles directional signal controlsuch time crystalline oscillations unidirectional propagation light
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Parameter Optimization Strategy for VSC-HVDC Low-Voltage Ride-Through Considering Short-CIRCUIT Current and System Stability
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作者 Zimin Zhu Yu Duan +3 位作者 Jian Ma Xiaoyun Wang Xiaoyu Deng Xiaofang Wu 《Energy Engineering》 2026年第4期321-340,共20页
When the converter bus voltage of a voltage source converter-based high voltage direct current(VSC-HVDC)system drops below a certain predetermined threshold,the system enters low-voltage ride-through(LVRT)mode to avoi... When the converter bus voltage of a voltage source converter-based high voltage direct current(VSC-HVDC)system drops below a certain predetermined threshold,the system enters low-voltage ride-through(LVRT)mode to avoid overcurrent and potential equipment failure,during which it operates as a controlled current source.The influence mechanism of LVRT control strategies on short-circuit current and overall system stability remains not yet fully and systematically investigated.First,this paper provides an overview of several LVRT strategies for VSC-HVDC systems and examines their effects on short-circuit current contribution.Next,it analyzes in detail the mechanisms through which active and reactive currents injected during LVRT impact system frequency stability,voltage stability,and synchronization stability.To address these interrelated issues,an optimized and comprehensive LVRT strategy incorporating short-circuit current constraints is proposed.The approach determines the active current ratio based on system frequency stability requirements and dynamically adjusts the active current recovery rate via phase control of the VSC-HVDC bus.The remaining capacity is allocated to reactive current support,thereby enhancing voltage and synchronization stability while maintaining sufficient short-circuit current margin and system frequency stability.Finally,simulations conducted on the PSS/E platform,using actual grid data from a selected cross-section system,validate convincingly the effectiveness of the proposed parameter optimization strategy for VSC-HVDC low-voltage ride-through. 展开更多
关键词 Short-circuit current VSC-HVDC systems LVRT voltage stability frequency stability synchronization stability
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Synchronization Stability Analysis of Multi-VSC Grid-connected System via Multi-scale Method
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作者 Meng Huang Yangjian Ling +3 位作者 Han Yan Xikun Fu Xiaoming Zha Herbert Ho-Ching Iu 《CSEE Journal of Power and Energy Systems》 2026年第1期282-293,共12页
In a multiple voltage source converter(VSC)system,the nonlinear characteristics of phase-locked loops(PLLs)and their interactions have a significant influence on the synchronization stability of converters.In this pap... In a multiple voltage source converter(VSC)system,the nonlinear characteristics of phase-locked loops(PLLs)and their interactions have a significant influence on the synchronization stability of converters.In this paper,these influences are investigated from the perspective of the time domain.First,a novel time-domain model of the multi-VSC system is obtained by using a multi-scale method.On this basis,a stability criterion is proposed to assess the synchronization stability of the system.Then,the accuracy of the time-domain model and its stability criterion in various conditions are discussed.Moreover,the negative impact of the interaction on the system is quantified.Finally,the above theoretical analysis is also verified in the controller hardware-in-the-loop(CHIL)experiments. 展开更多
关键词 Multi-scale method multi-VSC phase-locked loops synchronization stability time-domain model
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FIXED-TIME PASSIVITY AND SYNCHRONIZATION OF SPATIOTEMPORAL DIRECTED NETWORKS WITH MULTIPLE WEIGHTS
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作者 Yujie MA Cheng HU Leimin WANG 《Acta Mathematica Scientia》 2026年第1期361-382,共22页
This paper is dedicated to fixed-time passivity and synchronization for multi-weighted spatiotemporal directed networks.First,to achieve fixed-time passivity,a type of decentralized power-law controller is developed,i... This paper is dedicated to fixed-time passivity and synchronization for multi-weighted spatiotemporal directed networks.First,to achieve fixed-time passivity,a type of decentralized power-law controller is developed,in which only one parameter needs to be adjusted in the power-law terms;this greatly decreases the inconvenience of parameter adjustment.Second,several fixed-time passivity criteria with LMI forms are derived by using a Gauss divergence theorem to deal with the spatial diffusion of nodes and by applying the Hölder’s inequality to dispose rigorously the power-law term greater than one in the designed control scheme;this improves the previous theoretical analysis.Additionally,the fixed-time synchronization of spatiotemporal directed networks with multi-weights is addressed as a direct result of fixed-time strict passivity.Finally,a numerical example is presented in order to show the validity of the theoretical analysis. 展开更多
关键词 fixed-time passivity fixed-time synchronization spatiotemporal networks multiple weights directed topology
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