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Photomechanical movements of a coordination polymer-based composite enable a reversible photocontrollable electrical switch
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作者 Qian Ren Shu-Fen Zhang +1 位作者 Dong Liu Jian-Ping Lang 《Chinese Journal of Structural Chemistry》 2025年第7期67-73,共7页
Flexible circuit switches have been widely used in electronic devices due to their outstanding flexibility and operability.In order to expand the types of flexible circuit switch materials,we develop a unique composit... Flexible circuit switches have been widely used in electronic devices due to their outstanding flexibility and operability.In order to expand the types of flexible circuit switch materials,we develop a unique composite material,which integrates a photoresponsive flexible substrate derived from a photoreactive coordination polymer(CP)with an elastic conductive adhesive tape(CAT)in this work.The photoreactive CP{[Cd(2,6-bpvn)(3,5-DBB)_(2)]·DMF}_(n)(1)is prepared through solvothermal reaction of Cd(NO_(3))_(2)·4H_(2)O with 2,6-bis((E)-2-(pyridin-4-yl)vinyl)naphthalene(2,6-bpvn)and 3,5-dibromobenzoic acid(3,5-HDBB).Upon irradiation with UV light,crystals of 1 can undergo[2+2]photocycloaddition reaction and exhibit photomechanical movements.The crystalline powder of 1 can be uniformly distributed in polyvinyl alcohol(PVA)to generate the composite film 1-PVA.After pasting a piece of CAT on the surface of a 1-PVA film,a conductive two-layer film of 1-PVA/CAT can be fabricated.This film bends rapidly upon UV light exposure,connecting the circuit and causing the bulb to light up.When the light source is removed,it reverts to its initial state and the circuit is disconnected and the bulb is extinguished.This process can be cycled at least 100 times,achieving precise turn-on and turn-off performances of the photocontrollable circuit switch. 展开更多
关键词 Coordination polymer Photocycloaddition reaction Composite film Photomechanical movements Electrical switch
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Transcranial temporal interference stimulation precisely targets deep brain regions to regulate eye movements
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作者 Mo Wang Sixian Song +6 位作者 Dan Li Guangchao Zhao Yu Luo Yi Tian Jiajia Zhang Quanying Liu Pengfei Wei 《Neuroscience Bulletin》 2025年第8期1390-1402,共13页
Transcranial temporal interference stimulation(tTIS)is a novel non-invasive neuromodulation technique with the potential to precisely target deep brain structures.This study explores the neural and behavioral effects ... Transcranial temporal interference stimulation(tTIS)is a novel non-invasive neuromodulation technique with the potential to precisely target deep brain structures.This study explores the neural and behavioral effects of tTIS on the superior colliculus(SC),a region involved in eye movement control,in mice.Computational modeling revealed that tTIS delivers more focused stimulation to the SC than traditional transcranial alternating current stimulation.In vivo experiments,including Ca^(2+)signal recordings and eye movement tracking,showed that tTIS effectively modulates SC neural activity and induces eye movements.A significant correlation was found between stimulation frequency and saccade frequency,suggesting direct tTIS-induced modulation of SC activity.These results demonstrate the precision of tTIS in targeting deep brain regions and regulating eye movements,highlighting its potential for neuroscientific research and therapeutic applications. 展开更多
关键词 Temporal interference stimulation Superior colliculus Tissue phantom Finite element method Transcranial electrical stimulation Eye movement
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青藏高原地下水研究现状及主要科学问题
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作者 郭华明 高志鹏 +4 位作者 胡雅璐 邢世平 李遥 蒋小伟 彭建兵 《地学前缘》 北大核心 2026年第1期328-341,共14页
作为“亚洲水塔”的青藏高原,其地下水对于维持长江、黄河、雅鲁藏布江、怒江、澜沧江等亚洲大江大河的流量稳定、保障区域生态系统健康、确保数亿人口用水安全具有不可替代的作用。然而,相对于地表水和冰川冻土,青藏高原地下水研究十... 作为“亚洲水塔”的青藏高原,其地下水对于维持长江、黄河、雅鲁藏布江、怒江、澜沧江等亚洲大江大河的流量稳定、保障区域生态系统健康、确保数亿人口用水安全具有不可替代的作用。然而,相对于地表水和冰川冻土,青藏高原地下水研究十分薄弱。少数研究利用GRACE卫星数据反演,量化了地下水储量变化的发展趋势;部分研究揭示了冻融条件下局部区域地下水动态特征及生态环境效应。本文在对相关文献进行系统梳理的基础上,总结了青藏高原地下水类型及分布和地下水利用现状,粗略估算了地下水储量和地下水资源量,揭示了冰川冻土特殊环境下地下水地表水相互作用规律。最后,提出了青藏高原地下水研究存在的主要科学问题,包括浅表固态液态水转化通量和机制、青藏高原地下水循环深度、青藏高原地下水储量及其变化机制。这些科学问题的解决将提升对特殊气象水文、剧烈起伏地形地貌、复杂地质构造和水文地质条件下地下水赋存规律、循环特征及水热耦合过程等理论认识,进一步丰富水文地质学的理论体系。 展开更多
关键词 冰川 冻土 水资源 含水层 构造运动 地热
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基于动作捕捉技术分析神经根型颈椎病患者的颈椎运动特征
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作者 李智斐 韩斌 +4 位作者 柳秋丽 张展鸣 韦浩凯 左匡时 张翼升 《中国组织工程研究》 北大核心 2026年第9期2286-2293,共8页
背景:动作捕捉技术能够全方位、精准地剖析颈椎三维立体结构角度,并获取精确的数据,有助于深入了解神经根型颈椎病患者的颈椎运动特征,对于指导神经根型颈椎病的预防、辅助神经根型颈椎病诊断、制定个性化治疗方案以及指导康复训练具有... 背景:动作捕捉技术能够全方位、精准地剖析颈椎三维立体结构角度,并获取精确的数据,有助于深入了解神经根型颈椎病患者的颈椎运动特征,对于指导神经根型颈椎病的预防、辅助神经根型颈椎病诊断、制定个性化治疗方案以及指导康复训练具有至关重要的意义。目的:通过动作捕捉技术来探讨神经根型颈椎病患者的颈椎运动特征,揭示神经根型颈椎病的发病机制。方法:选择2023-10-01/2024-03-01在广西中医药大学第一附属医院骨科门诊就诊的神经根型颈椎病患者5例,为神经根型颈椎病组;健康人群5例,为健康对照组,记录所有研究对象的性别、年龄、头围、体质量指数。通过惯性测量单元磁场传感器捕捉研究对象颈部前屈、后伸、左屈、右屈、左旋、右旋6个自由度动作时角度变化过程(轨迹)及运动范围。结果与结论:①神经根型颈椎病组患者在颈椎前屈运动时C2-C7相对角度变化明显小于健康对照组(P<0.01);神经根型颈椎病组患者颈部运动误差范围在右旋时显著大于健康对照组(P<0.01);神经根型颈椎病组患者在做颈椎前屈运动时,屈曲到最大范围的时间要比恢复到正常体位的时间长(P<0.01);②神经根型颈椎病组患者在颈椎前屈、右旋运动时颈部运动范围明显小于健康对照组(P<0.001)。结果表明:神经根型颈椎病患者在颈椎运动时患侧肌肉及神经出现退变,肌肉肌力及协调能力降低,同时健侧肌肉及神经会代偿患侧的不足而出现控制过度的现象,与“筋骨失衡”的理念一致。 展开更多
关键词 神经根型颈椎病 颈椎运动 动作捕捉 惯性传感器 筋骨失衡 工程化组织构建
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Existence of Extracellular Calmodulin in the Lower Epidermis of the Leaves of Vicia faba and Its Role in Regulating Stomatal Movements
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作者 陈玉玲 张学琴 +1 位作者 陈珈 王学臣 《Acta Botanica Sinica》 CSCD 2003年第1期40-46,共7页
As a possible peptide primary messenger, extracellular calmodulin (CaM) may regulate processes such as cell proliferation, pollen germination and expression of some genes. Stomata open or close quickly in response to ... As a possible peptide primary messenger, extracellular calmodulin (CaM) may regulate processes such as cell proliferation, pollen germination and expression of some genes. Stomata open or close quickly in response to environmental stimuli. CaM was found to be extracellular both in guard cells of broad bean leaves and in epidermal cells by immuno-electron microscopy and immuno-fluorescence microscopy techniques. Exogenous purified CaM enhanced stomatal closure and inhibited stomatal opening with an optimal concentration of 10(-8) mol/L; CaM antagonist W7-agarose and anti-CaM serum, which were membrane-impermeable macromolecules, inhibited stomatal closure and promoted stomatal opening. All these data showed that endogenous extracellular CaM. of guard cells did promote stomatal closure and inhibit stomatal opening, and could he active only outside the cells. Therefore under natural conditions, the endogenous extracellular CaM of guard cells might regulate stomatal movements as a primary messenger together with other signal molecules, and might be an important linkage between environmental stimuli and cell responses. 展开更多
关键词 extracellular CaM Vicia faba stomatal movement
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Eye movements during inspecting pictures of natural scenes for information to verify sentences
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作者 陈庆荣 蒋志杰 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期444-447,共4页
As eye tracking can be used to record moment-to-moment changes of eye movements as people inspect pictures of natural scenes and comprehend information, this paper attempts to use eye-movement technology to investigat... As eye tracking can be used to record moment-to-moment changes of eye movements as people inspect pictures of natural scenes and comprehend information, this paper attempts to use eye-movement technology to investigate how the order of presentation and the characteristics of information affect the semantic mismatch effect in the picture-sentence paradigm. A 3(syntax)×2(semantic relation) factorial design is adopted, with syntax and semantic relations as within-participant variables. The experiment finds that the semantic mismatch is most likely to increase cognitive loads as people have to spend more time, including first-pass time, regression path duration, and total fixation duration. Double negation does not significantly increase the processing difficulty of pictures and information. Experimental results show that people can extract the special syntactic strategy from long-term memory to process pictures and sentences with different semantic relations. It enables readers to comprehend double negation as affirmation. These results demonstrate that the constituent comparison model may not be a general model regarding other languages. 展开更多
关键词 natural scene semantic mismatch double negation eye movement
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Neuromodulation techniques for modulating cognitive function:Enhancing stimulation precision and intervention effects
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作者 Hanwen Cao Li Shang +9 位作者 Deheng Hu Jianbing Huang Yu Wang Ming Li Yilin Song Qianzi Yang Yan Luo Ying Wang Xinxia Cai Juntao Liu 《Neural Regeneration Research》 2026年第2期491-501,共11页
Neuromodulation techniques effectively intervene in cognitive function,holding considerable scientific and practical value in fields such as aerospace,medicine,life sciences,and brain research.These techniques utilize... Neuromodulation techniques effectively intervene in cognitive function,holding considerable scientific and practical value in fields such as aerospace,medicine,life sciences,and brain research.These techniques utilize electrical stimulation to directly or indirectly target specific brain regions,modulating neural activity and influencing broader brain networks,thereby regulating cognitive function.Regulating cognitive function involves an understanding of aspects such as perception,learning and memory,attention,spatial cognition,and physical function.To enhance the application of cognitive regulation in the general population,this paper reviews recent publications from the Web of Science to assess the advancements and challenges of invasive and non-invasive stimulation methods in modulating cognitive functions.This review covers various neuromodulation techniques for cognitive intervention,including deep brain stimulation,vagus nerve stimulation,and invasive methods using microelectrode arrays.The non-invasive techniques discussed include transcranial magnetic stimulation,transcranial direct current stimulation,transcranial alternating current stimulation,transcutaneous electrical acupoint stimulation,and time interference stimulation for activating deep targets.Invasive stimulation methods,which are ideal for studying the pathogenesis of neurological diseases,tend to cause greater trauma and have been less researched in the context of cognitive function regulation.Non-invasive methods,particularly newer transcranial stimulation techniques,are gentler and more appropriate for regulating cognitive functions in the general population.These include transcutaneous acupoint electrical stimulation using acupoints and time interference methods for activating deep targets.This paper also discusses current technical challenges and potential future breakthroughs in neuromodulation technology.It is recommended that neuromodulation techniques be combined with neural detection methods to better assess their effects and improve the accuracy of non-invasive neuromodulation.Additionally,researching closed-loop feedback neuromodulation methods is identified as a promising direction for future development. 展开更多
关键词 acupuncture points ATTENTION brain COGNITION efficiency electrical stimulation MICROELECTRODES movement disorders nervous system PERCEPTION
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Low-density lipoprotein receptor–related protein 1 mediatesα-synuclein transmission from the striatum to the substantia nigra in animal models of Parkinson's disease
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作者 Hanjiang Luo Caixia Peng +5 位作者 Chengli Wu Chengwei Liu Qinghua Li Shun Yu Jia Liu Min Chen 《Neural Regeneration Research》 2026年第4期1595-1606,共12页
α-Synuclein accumulation and transmission are vital to the pathogenesis of Parkinson's disease,although the mechanisms underlying misfoldedα-synuclein accumulation and propagation have not been conclusively dete... α-Synuclein accumulation and transmission are vital to the pathogenesis of Parkinson's disease,although the mechanisms underlying misfoldedα-synuclein accumulation and propagation have not been conclusively determined.The expression of low-density lipoprotein receptor–related protein 1,which is abundantly expressed in neurons and considered to be a multifunctional endocytic receptor,is elevated in the neurons of patients with Parkinson's disease.However,whether there is a direct link between low-density lipoprotein receptor–related protein 1 andα-synuclein aggregation and propagation in Parkinson's disease remains unclear.Here,we established animal models of Parkinson's disease by inoculating monkeys and mice withα-synuclein pre-formed fibrils and observed elevated low-density lipoprotein receptor–related protein 1 levels in the striatum and substantia nigra,accompanied by dopaminergic neuron loss and increasedα-synuclein levels.However,low-density lipoprotein receptor–related protein 1 knockdown efficiently rescued dopaminergic neurodegeneration and inhibited the increase inα-synuclein levels in the nigrostriatal system.In HEK293A cells overexpressingα-synuclein fragments,low-density lipoprotein receptor–related protein 1 levels were upregulated only when the N-terminus ofα-synuclein was present,whereas anα-synuclein fragment lacking the N-terminus did not lead to low-density lipoprotein receptor–related protein 1 upregulation.Furthermore,the N-terminus ofα-synuclein was found to be rich in lysine residues,and blocking lysine residues in PC12 cells treated withα-synuclein pre-formed fibrils effectively reduced the elevated low-density lipoprotein receptor–related protein 1 andα-synuclein levels.These findings indicate that low-density lipoprotein receptor–related protein 1 regulates pathological transmission ofα-synuclein from the striatum to the substantia nigra in the nigrostriatal system via lysine residues in theα-synuclein N-terminus. 展开更多
关键词 Α-SYNUCLEIN dopaminergic neurodegeneration INTERNALIZATION low-density lipoprotein receptor-related protein 1 lysine pre-formed fibril movement disorder nigrostriatal system Parkinson's disease TRANSMISSION
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UGEA-LMD: A Continuous-Time Dynamic Graph Representation Enhancement Framework for Lateral Movement Detection
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作者 Jizhao Liu Yuanyuan Shao +2 位作者 Shuqin Zhang Fangfang Shan Jun Li 《Computers, Materials & Continua》 2026年第1期1924-1943,共20页
Lateral movement represents the most covert and critical phase of Advanced Persistent Threats(APTs),and its detection still faces two primary challenges:sample scarcity and“cold start”of new entities.To address thes... Lateral movement represents the most covert and critical phase of Advanced Persistent Threats(APTs),and its detection still faces two primary challenges:sample scarcity and“cold start”of new entities.To address these challenges,we propose an Uncertainty-Driven Graph Embedding-Enhanced Lateral Movement Detection framework(UGEA-LMD).First,the framework employs event-level incremental encoding on a continuous-time graph to capture fine-grained behavioral evolution,enabling newly appearing nodes to retain temporal contextual awareness even in the absence of historical interactions and thereby fundamentally mitigating the cold-start problem.Second,in the embedding space,we model the dependency structure among feature dimensions using a Gaussian copula to quantify the uncertainty distribution,and generate augmented samples with consistent structural and semantic properties through adaptive sampling,thus expanding the representation space of sparse samples and enhancing the model’s generalization under sparse sample conditions.Unlike static graph methods that cannot model temporal dependencies or data augmentation techniques that depend on predefined structures,UGEA-LMD offers both superior temporaldynamic modeling and structural generalization.Experimental results on the large-scale LANL log dataset demonstrate that,under the transductive setting,UGEA-LMD achieves an AUC of 0.9254;even when 10%of nodes or edges are withheld during training,UGEA-LMD significantly outperforms baseline methods on metrics such as recall and AUC,confirming its robustness and generalization capability in sparse-sample and cold-start scenarios. 展开更多
关键词 Advanced persistent threat(APTs) lateral movement detection continuous-time dynamic graph data enhancement
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Far-field crustal movements before and after the 2011 Ms9.0 Japan earthquake from GPS observations 被引量:14
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作者 Gu Guohua Wang Wuxing 《Geodesy and Geodynamics》 2011年第3期1-7,共7页
The paper gives an analysis of the displacement time series before and after the March 11,2011 Ms9.0 east Japan earthquake and co-seismic displacements observed at continuous GPS stations in and around China. The resu... The paper gives an analysis of the displacement time series before and after the March 11,2011 Ms9.0 east Japan earthquake and co-seismic displacements observed at continuous GPS stations in and around China. The results showed a broad-scaled related elastic-rebound process and some premonitory horizontal crustal movements to this earthquake over this vast area. 展开更多
关键词 Japan earthquake crustal movement GPS earthquake prediction co-seismic displacement
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Using Quantile Regression Approach to Analyze Price Movements of Agricultural Products in China 被引量:7
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作者 LI Gan-qiong XU Shi-wei +2 位作者 LI Zhe-min SUN Yi-guo DONG Xiao-xia 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第4期674-683,共10页
This paper studies how the price movements of pork,chicken and egg respond to those of related cost factors in short terms in Chinese market.We employ a linear quantile approach not only to explore potential data hete... This paper studies how the price movements of pork,chicken and egg respond to those of related cost factors in short terms in Chinese market.We employ a linear quantile approach not only to explore potential data heteroscedasticity but also to generate confidence bands for the purpose of price stability study.We then evaluate our models by comparing the prediction intervals generated from the quantile regression models with in-sample and out-of-sample forecasts.Using monthly data from January 2000 to October 2010,we observed these findings:(i) the price changes of cost factors asymmetrically and unequally influence those of the livestock across different quantiles;(ii) the performance of our models is robust and consistent for both in-sample and out-of-sample forecasts;(iii) the confidence intervals generated from 0.05th and 0.95th quantile regression models are good methods to forecast livestock price fluctuation. 展开更多
关键词 cost factors agricultural products forecasting price movements quantile regression model
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Anomalous crustal movements before great Wenchuan earthquake observed by GPS 被引量:10
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作者 Gu Guohua Meng Guojie Wang Wuxing 《Geodesy and Geodynamics》 2011年第2期13-22,共10页
Studies of GPS data carried out before and after the great Wenchuan earthquake of Ms8.0 on May 12, 2008 show that anomalous crustal movements occurred before the earthquake. Data from 4 pre-earthquake observation sess... Studies of GPS data carried out before and after the great Wenchuan earthquake of Ms8.0 on May 12, 2008 show that anomalous crustal movements occurred before the earthquake. Data from 4 pre-earthquake observation sessions at a dense network of stations show that there were prominent broad-ranged long- and midterm anomalies in horizontal displacements and strain and in vertical displacements. Data from the fewer-numbered reference stations of continuous GPS observations since 1999 in West and South China showed short-term preseismic anomalies in horizontal displacements. The detection of co-seismic horizontal displacements at these stations supports the existence of the pre-earthquake anomalies. Results of single-epoch solutions of data from continuous-observation stations near the epicenter also show large imminent anomalies in vertical displacements. Although the Wenchuan earthquake was not predicted, these results give a strong indication that GPS should be the main observation technique for long-term, mid-term, short-term and imminent earthquake predictions. 展开更多
关键词 Wenchuan earthquake earthquake prediction GPS crustal movement horizontal displace- ment vertical displacement
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Mass movements in small canyons in the northeast of Baiyun deepwater area, north of the South China Sea 被引量:4
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作者 LI Xishuang LIU Lejun +3 位作者 LI Jiagang GAO Shan ZHOU Qingjie SU Tianyun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第8期35-42,共8页
The process of mass movements and their consequent turbidity currents in large submarine canyons has been widely reported, however, little attention was paid to that in small canyons. In this paper, we document mass m... The process of mass movements and their consequent turbidity currents in large submarine canyons has been widely reported, however, little attention was paid to that in small canyons. In this paper, we document mass movements in small submarine canyons in the northeast of Baiyun deepwater area, north of the South China Sea (SCS), and their strong effects on the evolution of the canyons based on geophysical data. Submarine canyons in the study area arrange closely below the shelf break zone which was at the depth of -500 m. Within submarine canyons, seabed surface was covered with amounts of failure scars resulted from past small-sized landslides. A complex process of mass transportation in the canyons is indicated by three directions of mass movements. Recent mass movement deposits in the canyons exhibit translucent reflections or parallel reflections which represent the brittle deformation and the plastic deformation, respectively. The area of most landslides in the canyons is less than 3 km2. The trigger mechanisms for mass movements in the study area are gravitational overloading, slope angle and weak properties of soil. Geophysical data indicate that the genesis of submarine canyons is the erosion of mass movements and consequent turbidity currents. The significant effects of mass movements on canyon are incision and sediment transportation at the erosion phases and fillings supply at the fill phases. This research will be helpful for the geological risk assessments and understanding the sediment transportation in the northern margin of the SCS. 展开更多
关键词 mass movement geophysical data trigger mechanism submarine canyon north of the South China Sea
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Modeling and simulation of high-speed passenger train movements in the rail line 被引量:3
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作者 曹成铉 许琰 李克平 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第6期239-245,共7页
In this paper, we propose a new formula of the real-time minimum safety headway based on the relative velocity of consecutive trains and present a dynamic model of high-speed passenger train movements in the rail line... In this paper, we propose a new formula of the real-time minimum safety headway based on the relative velocity of consecutive trains and present a dynamic model of high-speed passenger train movements in the rail line based on the proposed formula of the minimum safety headway. Moreover, we provide the control strategies of the high-speed passenger train operations based on the proposed formula of the real-time minimum safety headway and the dynamic model of highspeed passenger train movements. The simulation results demonstrate that the proposed control strategies of the passenger train operations can greatly reduce the delay propagation in the high-speed rail line when a random delay occurs. 展开更多
关键词 SIMULATION dynamic model control strategies of train movements high-speed passenger train
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Eye Movements, Cognitive Processes, and Reading 被引量:6
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作者 Keith Rayner 《心理与行为研究》 2004年第3期482-488,共7页
关键词 eye movements perceptual SPAN INTEGRATION ACROSS SACCADES eye MOVEMENT control.
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Technical parameters of drawing and coal-gangue field movements of a fully mechanized large mining height top coal caving working face 被引量:7
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作者 LIU Chang-you HUANG Bing-xiang WU Feng-feng 《Mining Science and Technology》 EI CAS 2009年第5期549-555,共7页
Under fully mechanized, large mining height top coal caving conditions, the shield beam slope angle of the support increases due to the enlargement of the top coal breaking and caving space. This results in a change o... Under fully mechanized, large mining height top coal caving conditions, the shield beam slope angle of the support increases due to the enlargement of the top coal breaking and caving space. This results in a change of the caving window location and dimensions and, therefore, the granular coal-gangue movement and flows provide new characteristics during top coal caving. The main inferences we draw are as follows. Firstly, after shifting the supports, the caved top coal layer line and the coal gangue boundary line become steeper and are clearly larger than those under common mining heights. Secondly, during the top coal caving procedure, the speed of the coal-gangue flow increases and at the same drawing interval, the distance between the coal-gangue boundary line and the top beam end is reduced. Thirdly, affected by the drawing ratio, the slope angle of the shield beam and the dimensions of the caving window, it is easy to mix the gangue. A rational drawing interval will cause the coal-gangue boundary line to be slightly behind the down tail boom lower boundary. This rational drawing interval under conditions of large mining heights has been analyzed and determined. 展开更多
关键词 large mining height top coal caving coal-gangue movement field coal caving technical parameters coal caving window
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Energy-optimal control model for train movements 被引量:3
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作者 李克平 高自友 毛保华 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第2期359-364,共6页
In this paper, we propose a new cellular automaton (CA) model for train movement simulations under mixed traffic conditions. A kind of control strategy is employed for trains to reduce energy consumption. In the pro... In this paper, we propose a new cellular automaton (CA) model for train movement simulations under mixed traffic conditions. A kind of control strategy is employed for trains to reduce energy consumption. In the proposed CA model, the driver controls the train movements by using some updated rules. In order to obtain a good insight into the evolution behaviours of the rail traffic flow, we investigate the space-time diagram of the rail traffic flow and the trajectories of the train movements. The numerical simulation results demonstrate that the proposed CA model can well describe the dynamic behaviours of the train movements. Some complex phenomena of train movements can be reproduced, such as the train delay propagations, etc. 展开更多
关键词 train movement cellular automaton moving-block
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Frequency Ratio Analysis of Mass Movements in the Xiangxi Catchment, Three Gorges Reservoir Area, China 被引量:2
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作者 Dominik Ehret Joachim Rohn +7 位作者 Christian Dumperth Susan Eckstein Stefanie Ernstberger Karel Otte René Rudolph Johannes Wiedenmann 项伟 毕仁能 《Journal of Earth Science》 SCIE CAS CSCD 2010年第6期824-834,共11页
In 2003, the Three Gorges Project (TGP, China), currently the world's largest hydroelectric power plant by total capacity, went into operation. Due to large-scale impoundment of the Yangtze River and its tributarie... In 2003, the Three Gorges Project (TGP, China), currently the world's largest hydroelectric power plant by total capacity, went into operation. Due to large-scale impoundment of the Yangtze River and its tributaries and also due to resettlement, extensive environmental impacts like land use change and increase of geohazards are associated with the TGP. Within the Yangtze Project, we investigate these effects for the Xiangxi (香溪) catchment which is part of the Three Gorges Reservoir. The aim of this study is to evaluate the susceptibility for mass movement within the Xiangxi River backwater area using geographic information system (GIS). We used existing mass movements and the conditioning factors (geology, elevation, slope, curvature, land use, and land use change) for analyzing mass movement susceptibility. Mass movements and geology were mapped in the field to establish a mass movement inventory and a geological map. Land use and digital elevation model (DEM) were obtained from remote-sensing data. We determined the relation between mass movements and the conditioning factors by using the frequency ratio method and found strong relation between mass movements and both natural and human-influenced conditioning factors. 展开更多
关键词 mass movement SUSCEPTIBILITY GIS frequency ratio Xiangxi catchment Three Gorges Reservoir.
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Observations of coastal aeolian dune movements at Feicuidao, on the Changli Gold Coast in Hebei Province 被引量:3
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作者 YuXiang Dong DeQuan Huang JianHui Du 《Research in Cold and Arid Regions》 CSCD 2013年第3期324-330,共7页
High-precision RTK GPS technology was used to survey the movements of typical coastal dunes, including a coastal crescent dune and a coastal transverse ridge, in the Feicuidao region of the Changli Gold Coast in Hebei... High-precision RTK GPS technology was used to survey the movements of typical coastal dunes, including a coastal crescent dune and a coastal transverse ridge, in the Feicuidao region of the Changli Gold Coast in Hebei Province in 2006-2008. Our data provide information on the direction, type, and velocity of coastal dune movements, and indicate that the coastal dunes in this re- gion are characterized as slow and landward advancing, with to-and-fro fluctuations. The bottom of the studied coastal transverse ridge was stable during the observation period but the position of its crest advanced eastward (seaward) during summer and au- tumn, and moved landward (westward) in winter and spring. Thus, its crest moved generally landward (westward) but fluctuated to-and-fro eastward and westward. In contrast, the entire coastal crescent dune advanced landward (westward) in a to-and-fro manner, and the velocity of its movement was faster than that of the transverse ridge dune. These results are mainly related to the wind conditions in the research area, the height and volume of the two types of coastal dunes. 展开更多
关键词 coastal dune MOVEMENT observation Changli in Hebei Province
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Earth crust vertical movements according to ITRF2000, ITRF2005,ITRF2008 and ITRF2014 coordinate systems and their comparing analysis 被引量:3
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作者 N.A.Chujkova T.G.Maximova +1 位作者 T.S.Chesnokova A.N.Grushinsky 《Geodesy and Geodynamics》 2018年第2期109-114,共6页
The analysis of Earth’s crust movement vertical velocities was made both for separate regions, and averaged on regions. As input data coordinates and velocities of earth crust points, obtained in International Coordi... The analysis of Earth’s crust movement vertical velocities was made both for separate regions, and averaged on regions. As input data coordinates and velocities of earth crust points, obtained in International Coordinate Systems ITRF2000, ITRF2005,ITRF2008 on the base of processing radio interferometric(VLBI), laser(SLR), Doppler(DORIS) and GPS observations was used. For the purpose of global analysis all input velocity values were averaged in the x trapezoids. For filling trapezoids the spherical function expansion to N=36 was made. Expansion harmonic coefficients allowed determine the global characteristics of earth crust movements both for all Earth, and for separate hemispheres, polar and equatorial regions, continents and oceans. It appears, that polar regions were risen, and equatorial ones were lowered, that can indicate the modern Earth oblateness reduction. The constructed maps of vertical velocities were compared with obtained by us map of earth crust strain distribution. It is appeared, that regions of modern earth surface rising(Fennoscandia, Canada, Antarctica) coincide with regions of vertical extension strain, and the lowering regions-with compression regions. Simultaneously with the determination of harmonious coefficients the mean-square error of approximation for expansion of power n=1 N and power dispersion were determined. Whereas the results converge badly and dispersion increased with the n grows, hence we can concludes, that vertical movements do not characterized global earth crust movement and denotes the unrelated character of these movement. Seemingly, the main cause of such movement origin is the local seismic events(earthquake, volcanic eruption and so on). It confirms by our conclusions about correspondence of vertical strain maximal gradient(and therefore vertical velocities) map of the earthquake distribution. In work the detailed analysis of obtained results for separate Earth’s regions was made. 展开更多
关键词 Crust movement Coordinate system UPLIFT
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