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Long-range electron synergy over Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst in enhancing charge separation for photocatalytic hydrogen production 被引量:2
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作者 Man Yang Jing Mei +3 位作者 Yujing Ren Jie Cui Shuhua Liang Shaodong Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期502-509,I0011,共9页
The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.He... The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.Herein,we fabricate Pt and Co single-atom sites successively on polymeric carbon nitride(CN).In this Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst,the noble-metal active sites are maximized,and the single-atomic Co_(1)N_4sites are tuned to Co_(1)N_3sites by photogenerated electrons arising from the introduced single-atomic Pt_(1)N_4sites.Mechanism studies and density functional theory(DFT)calculations reveal that the 3d orbitals of Co_(1)N_3single sites are filled with unpaired d-electrons,which lead to the improved visible-light response,carrier separation and charge migration for CN photocatalysts.Thereafter,the protons adsorption and activation are promoted.Taking this advantage of long-range electron synergy in bimetallic single atomic sites,the photocatalytic hydrogen evolution activity over Pt_(1)-Co_(1)/CN achieves 915.8 mmol g^(-1)Pt h^(-1),which is 19.8 times higher than Co_(1)/CN and 3.5 times higher to Pt_(1)/CN.While this electron-synergistic effect is not so efficient for Pt nanoclusters.These results demonstrate the synergistic effect at electron-level and provide electron-level guidance for the design of efficient photocatalysts. 展开更多
关键词 Bimetallic single-atom catalyst long-range electron synergy Charge separation/transfer Carbon nitride Hydrogen production
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Topological properties of tetratomic Su-Schrieffer-Heeger chains with hierarchical long-range hopping
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作者 李冠强 王博涵 +2 位作者 唐劲羽 彭娉 董亮伟 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期469-476,共8页
We propose a new generalized Su–Schrieffer–Heeger model with hierarchical long-range hopping based on a onedimensional tetratomic chain. The properties of the topological states and phase transition, which depend on... We propose a new generalized Su–Schrieffer–Heeger model with hierarchical long-range hopping based on a onedimensional tetratomic chain. The properties of the topological states and phase transition, which depend on the cointeraction of the intracell and intercell hoppings, are investigated using the phase diagram of the winding number. It is shown that topological states with large positive/negative winding numbers can readily be generated in this system. The properties of the topological states can be verified by the ring-type structures in the trajectory diagram of the complex plane. The topological phase transition is strongly related to the opening(closure) of an energy bandgap at the center(boundaries) of the Brillouin zone. Finally, the non-zero-energy edge states at the ends of the finite system are revealed and matched with the bulk–boundary correspondence. 展开更多
关键词 generalized Su-Schrieffer-Heeger model tight-binding approximation topological phase transition long-range hopping winding number edge state
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Generalized uncertainty principle from long-range kernel effects:The case of the Hawking black hole temperature
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作者 Rami Ahmad El-Nabulsi Waranont Anukool 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期153-156,共4页
We prove the existence of an analogy between spatial long-range interactions,which are of the convolution-type introduced in non-relativistic quantum mechanics,and the generalized uncertainty principle predicted from ... We prove the existence of an analogy between spatial long-range interactions,which are of the convolution-type introduced in non-relativistic quantum mechanics,and the generalized uncertainty principle predicted from quantum gravity theories.As an illustration,black hole temperature effects are discussed.It is observed that for specific choices of the moment's kernels,cold black holes may emerge in the theory. 展开更多
关键词 long-range kernel effects generalized uncertainty principle
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Ag、Cu、Au、Ni、Pd、Pt的Long-range Finis-Sinclair势构建及其二元合金形成焓的计算
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作者 刘艳侠 顾慧 +2 位作者 刘磊 孙佳佳 高岩 《辽宁大学学报(自然科学版)》 CAS 2009年第3期193-196,共4页
构建了fcc金属Cu、Ag、Au、Ni、Pd、Pt的Long-range Finnis-Sinclair势,并利用晶格常数、体弹性模量和金属的内聚能的实验数据拟合了这几种金属的Long-range Finnis-Sinclair势参数;利用Miedema理论和所构建的原子间相互作用势计算了Cu,... 构建了fcc金属Cu、Ag、Au、Ni、Pd、Pt的Long-range Finnis-Sinclair势,并利用晶格常数、体弹性模量和金属的内聚能的实验数据拟合了这几种金属的Long-range Finnis-Sinclair势参数;利用Miedema理论和所构建的原子间相互作用势计算了Cu,Ag,Au,Ni,Pd,Pt的二元合金的形成焓.对两种计算结果进行了比较,并与已有的实验结果进行了比较.结果表明,使用Long-range Finnis-Sinclair势计算合金的形成焓能够得到令人满意的结果. 展开更多
关键词 long-range Finnis-Sinclair势 MIEDEMA理论 形成焓
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SwinFusion: Cross-domain Long-range Learning for General Image Fusion via Swin Transformer 被引量:17
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作者 Jiayi Ma Linfeng Tang +3 位作者 Fan Fan Jun Huang Xiaoguang Mei Yong Ma 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第7期1200-1217,共18页
This study proposes a novel general image fusion framework based on cross-domain long-range learning and Swin Transformer,termed as SwinFusion.On the one hand,an attention-guided cross-domain module is devised to achi... This study proposes a novel general image fusion framework based on cross-domain long-range learning and Swin Transformer,termed as SwinFusion.On the one hand,an attention-guided cross-domain module is devised to achieve sufficient integration of complementary information and global interaction.More specifically,the proposed method involves an intra-domain fusion unit based on self-attention and an interdomain fusion unit based on cross-attention,which mine and integrate long dependencies within the same domain and across domains.Through long-range dependency modeling,the network is able to fully implement domain-specific information extraction and cross-domain complementary information integration as well as maintaining the appropriate apparent intensity from a global perspective.In particular,we introduce the shifted windows mechanism into the self-attention and cross-attention,which allows our model to receive images with arbitrary sizes.On the other hand,the multi-scene image fusion problems are generalized to a unified framework with structure maintenance,detail preservation,and proper intensity control.Moreover,an elaborate loss function,consisting of SSIM loss,texture loss,and intensity loss,drives the network to preserve abundant texture details and structural information,as well as presenting optimal apparent intensity.Extensive experiments on both multi-modal image fusion and digital photography image fusion demonstrate the superiority of our SwinFusion compared to the state-of-theart unified image fusion algorithms and task-specific alternatives.Implementation code and pre-trained weights can be accessed at https://github.com/Linfeng-Tang/SwinFusion. 展开更多
关键词 Cross-domain long-range learning image fusion Swin transformer
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The influence of magnetic field on the beam quality of relativistic electron beam long-range propagation in near-Earth environment 被引量:2
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作者 郝建红 王希 +4 位作者 张芳 赵强 范杰清 薛碧曦 董志伟 《Plasma Science and Technology》 SCIE EI CAS CSCD 2021年第11期42-49,共8页
In recent years,it has been proposed to use satellite-mounted radio-frequency(RF)accelerators to produce high-current relativistic electron beams to complete debris removal tasks.However,when simulating the long-range... In recent years,it has been proposed to use satellite-mounted radio-frequency(RF)accelerators to produce high-current relativistic electron beams to complete debris removal tasks.However,when simulating the long-range propagation(km-range)process of the electron beam,it is difficult to directly use the particle-in-cell method to simultaneously consider the space charge effect of beam and the influence of the geomagnetic field.Owing to these limitations,in this paper,we proposed a simplified method.The ps-range electronic micropulses emitted by the RF accelerator were transmitted and fused to form a ns-range electron beam;then,combined with the improved moving window technology,the model was constructed to simulate the long-range propagation process of the relativistic electron beam in near-Earth environment.Finally,by setting the direction of movement of the beam to be parallel,perpendicular and at an inclination of 3°to the magnetic field,we analyzed and compared the effects of the applied magnetic fields in different directions on the quality of the beam during long-range propagation.The simulation results showed that the parallel state of the beam motion and magnetic fields should be achieved as much as possible to ensure the feasibility of the space debris removal. 展开更多
关键词 space debris relativistic electron beam long-range propagation geomagnetic field radio frequency accelerator
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A Long-Range Generalized Predictive Control Algorithm for a DFIG Based Wind Energy System 被引量:1
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作者 J.S.Solis-Chaves Lucas L.Rodrigues +1 位作者 C.M.Rocha-Osorio Alfeu J.Sguarezi Filho 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第5期1209-1219,共11页
This paper presents a new Long-range generalized predictive controller in the synchronous reference frame for a wind energy system doubly-fed induction generator based. This controller uses the state space equations t... This paper presents a new Long-range generalized predictive controller in the synchronous reference frame for a wind energy system doubly-fed induction generator based. This controller uses the state space equations that consider the rotor current and voltage as state and control variables, to execute the predictive control action. Therefore, the model of the plant must be transformed into two discrete transference functions, by means of an auto-regressive moving average model, in order to attain a discrete and decoupled controller, which makes it possible to treat it as two independent single-input single-output systems instead of a magnetic coupled multiple-input multiple-output system. For achieving that, a direct power control strategy is used, based on the past and future rotor currents and voltages estimation. The algorithm evaluates the rotor current predictors for a defined prediction horizon and computes the new rotor voltages that must be injected to controlling the stator active and reactive powers. To evaluate the controller performance, some simulations were made using Matlab/Simulink. Experimental tests were carried out with a small-scale prototype assuming normal operating conditions with constant and variable wind speed profiles. Finally, some conclusions respect to the dynamic performance of this new controller are summarized. 展开更多
关键词 Direct power CONTROL DOUBLY-FED induction GENERATOR flux oriented CONTROL generalized PREDICTIVE CONTROL long-range PREDICTIVE CONTROL wind energy systems
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Preliminary research on the relationship between long-range correlations and predictability 被引量:1
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作者 张志森 龚志强 +2 位作者 支蓉 封国林 胡经国 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期23-32,共10页
By establishing the Markov model for a long-range correlated time series (LRCS) and analysing its evolutionary characteristics, this paper defines a physical effective correlation length (ECL) T, which reflects th... By establishing the Markov model for a long-range correlated time series (LRCS) and analysing its evolutionary characteristics, this paper defines a physical effective correlation length (ECL) T, which reflects the predictability of the LRCS. It also finds that the ECL has a better power law relation with the long-range correlated exponent γ of the LRCS: T = Kexp(-γ/0.3) + Y, (0 〈 γ〈 1) the predictability of the LRCS decays exponentially with the increase of γ It is then applied to a daily maximum temperature series (DMTS) recorded at 740 stations in China between the years 1960-2005 and calculates the ECL of the DMTS. The results show the remarkable regional distributive feature that the ECL is about 10-14 days in west, northwest and northern China, and about 5-10 days in east, southeast and southern China. Namely, the predictability of the DMTS is higher in central-west China than in east and southeast China. In addition, the ECL is reduced by 1-8 days in most areas of China after subtracting the seasonal oscillation signal of the DMTS from its original DMTS; however, it is only slightly altered when the decadal linear trend is removed from the original DMTS. Therefore, it is shown that seasonal oscillation is a significant component of daily maximum temperature evolution and may provide a basis for predicting daily maximum temperatures. Seasonal oscillation is also significant for guiding general weather predictions, as well as seasonal weather predictions. 展开更多
关键词 long-range correlation information entropy effective correlation length PREDICTABILITY
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THE VLASOV-POISSON-BOLTZMANN SYSTEM NEAR MAXWELLIANS FOR LONG-RANGE INTERACTIONS 被引量:1
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作者 王路生 肖清华 +1 位作者 熊林杰 赵会江 《Acta Mathematica Scientia》 SCIE CSCD 2016年第4期1049-1097,共49页
In this article, we are concerned with the construction of global smooth small-amplitude solutions to the Cauchy problem of the one species Vlasov-Poisson-Boltzmann system near Maxwellians for long-range interactions.... In this article, we are concerned with the construction of global smooth small-amplitude solutions to the Cauchy problem of the one species Vlasov-Poisson-Boltzmann system near Maxwellians for long-range interactions. Compared with the former result obtained by Duan and Liu in [12] for the two species model, we do not ask the initial perturbation to satisfy the neutral condition and our result covers all physical collision kernels for the full range of intermolecular repulsive potentials. 展开更多
关键词 One-species Vlasov-Poisson-Boltzmann system long-range interactions global solutions near Maxwellians time-velocity weighted energy method
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Self-sustained target waves in excitable media with only a long-range link 被引量:1
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作者 钱郁 王参军 +2 位作者 石虎山 弭元元 黄晓东 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期457-462,共6页
In this paper we investigate spatiotemporal pattern formation in excitable media with only a long-range link. Besides the trivial solutions of spiral patterns, we find the asymptotic self-sustained target waves in the... In this paper we investigate spatiotemporal pattern formation in excitable media with only a long-range link. Besides the trivial solutions of spiral patterns, we find the asymptotic self-sustained target waves in the autonomous tissues. The wave source supporting this kind of new pattern is the oscillatory one-dimensional Winfree-loop self- organized under the presence of a long-range link, which is explored by the dominant phase-advanced driving method. Based on this understanding we can effectively regulate the oscillations of excitable media by suitably arranging the long-range link, including construction of self-sustained target waves with controllable period and wave length, or manipulation of system states between different patterns. 展开更多
关键词 self-sustained target waves long-range link one-dimensional Winfree-loop
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Analysis of Long-Range Transmission Loss in the West Pacific Ocean 被引量:1
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作者 吴丽丽 彭朝晖 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第9期74-78,共5页
A long-range sound propagation experiment was conducted in the West Pacific Ocean in July 2013. Linear frequency-modulated signals with a frequency band of 260-360Hz were transmitted by a transducer hung on a floating... A long-range sound propagation experiment was conducted in the West Pacific Ocean in July 2013. Linear frequency-modulated signals with a frequency band of 260-360Hz were transmitted by a transducer hung on a floating ship during the experiment and were received by a horizontal line array towed by another ship sailing away from the transducer. The maximum distance between the two ships was 1029km. Signals were received at the distances 34-220 kin, 612-635 km and 926-1029 kin. Transmission loss versus distance between source and receiver was obtained and compared with the theoretical results predicted by the parabolic equation method program RAM. It is shown that RAM is adequate for estimating the transmission loss for distances up to 1029km. When the water depth is larger than the surface conjugate depth, the ocean bottom rarely influences the transmission loss in the convergence zones. However, in the opposite situation, the ocean bottom contributes significantly to the transmission loss. 展开更多
关键词 Analysis of long-range Transmission Loss in the West Pacific Ocean
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Dynamics of the Random Ising Model with Long-Range Interaction
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作者 CHEN Yuan LI Zhi-Bing FANG Hai HE Shun-Shan SITU Shu-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第10期469-472,共4页
Critical dynamics of the random Ising model with long-range interaction decaying as r-(d+σ) where d is the dimensionality) is studied by the theoretic renormalization-group approach. The system is released to an evol... Critical dynamics of the random Ising model with long-range interaction decaying as r-(d+σ) where d is the dimensionality) is studied by the theoretic renormalization-group approach. The system is released to an evolution within a model A dynamics. Asymptotic scaling laws are studied in a frame of the expansion in = 2σ - d. In dimensions d < 2σ. the dynamic exponent z is calculated to the second order in at the random fixed point. 展开更多
关键词 ISING model critical dynamics long-range interaction quenched IMPURITIES
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Electronic properties of one-dimensional systems with long-range correlated binary potentials
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作者 Gong Long-Yan Tong Pei-Qing Zhou Zi-Cong 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第8期335-339,共5页
We study numerically the electronic properties of one-dimensional systems with long-range correlated binary potentials. The potentials are mapped from binary sequences with a power-law power spectrum over the entire f... We study numerically the electronic properties of one-dimensional systems with long-range correlated binary potentials. The potentials are mapped from binary sequences with a power-law power spectrum over the entire frequency range, which is characterized by correlation exponent β. We find the localization length ζ increases withβ. At system sizes N →∞, there are no extended states. However, there exists a transition at a threshold ζ. Whenβ 〉 βc, we obtain ζ 〉 0. On the other hand, at finite system sizes, ζ≥ N may happen at certain β, which makes the system "metallic", and the upper-bound system size N* (β) is given. 展开更多
关键词 electronic properties long-range correlation binary potentials LOCALIZATION
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Exact solutions of non-Hermitian chains with asymmetric long-range hopping under specific boundary conditions
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作者 郭翠仙 陈澍 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期81-86,共6页
We study the one-dimensional general non-Hermitian models with asymmetric long-range hopping and explore how to analytically solve the systems under some specific boundary conditions.Although the introduction of long-... We study the one-dimensional general non-Hermitian models with asymmetric long-range hopping and explore how to analytically solve the systems under some specific boundary conditions.Although the introduction of long-range hopping terms prevents us from finding analytical solutions for arbitrary boundary parameters,we identify the existence of exact solutions when the boundary parameters fulfill some constraint relations,which give the specific boundary conditions.Our analytical results show that the wave functions take simple forms and are independent of hopping range,while the eigenvalue spectra display rich model-dependent structures.Particularly,we find the existence of a special point coined as pseudo-periodic boundary condition,for which the eigenvalues are the same as those of the periodical system when the hopping parameters fulfill certain conditions,whereas the eigenstates display the non-Hermitian skin effect. 展开更多
关键词 non-Hermitian physics exact solution topological physics long-range hopping
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High resolution photoassociation spectra of an ultracold Cs_2 long-range 0_u^+ (6S_(1/2)+6P_(1/2) ) state
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作者 陈鹏 李玉清 +4 位作者 张一驰 武寄洲 马杰 肖连团 贾锁堂 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期376-380,共5页
In this paper, ultracold cesium molecules are formed through photoassociation technology, which is carried out in a magneto-optical trap. High resolution photoassociaion spectra with the rotational progressions up to ... In this paper, ultracold cesium molecules are formed through photoassociation technology, which is carried out in a magneto-optical trap. High resolution photoassociaion spectra with the rotational progressions up to J = 7 are obtained. Three rovibrational levels of the long-range 0+ state of Cs2 below the (6S1/2 + 6P1/2) dissociation limit are specifically investigated. By fitting their binding energy intervals to the non-rigid rotational model, the rotational constant of the long- range 0u+ state is determined. A proportional dependence of the value of the rotational constant on the vibrational quantum number is demonstrated. 展开更多
关键词 ultracold molecules PHOTOASSOCIATION trap-loss spectrum long-range molecular coefficient
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Simulation study on characteristics of long-range interaction in randomly asymmetric exclusion process
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作者 赵仕波 刘明哲 杨兰英 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第4期106-110,共5页
In this paper we investigate the dynamics of an asymmetric exclusion process on a one-dimensional lattice with long- range hopping and random update via Monte Carlo simulations theoretically. Particles in the model wi... In this paper we investigate the dynamics of an asymmetric exclusion process on a one-dimensional lattice with long- range hopping and random update via Monte Carlo simulations theoretically. Particles in the model will firstly try to hop over successive unoccupied sites with a probability q, which is different from previous exclusion process models. The probability q may represent the random access of particles. Numerical simulations for stationary particle currents, density profiles, and phase diagrams are obtained. There are three possible stationary phases: the low density (LD) phase, high density (HD) phase, and maximal current (MC) in the system, respectively. Interestingly, bulk density in the LD phase tends to zero, while the MC phase is governed by α,β, and q. The HD phase is nearly the same as the normal TASEP, determined by exit rate β. Theoretical analysis is in good agreement with simulation results. The proposed model may provide a better understanding of random interaction dynamics in complex systems. 展开更多
关键词 exclusion process Monte Carlo simulation random update long-range hopping
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Long-range correlation analysis of urban traffic data
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作者 盛鹏 王俊峰 +1 位作者 唐铁桥 赵树龙 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期55-64,共10页
This paper investigates urban traffic data by analysing the long-range correlation with detrended fluctuation analysis. Through a large number of real data collected by the travel time detection system in Beijing, the... This paper investigates urban traffic data by analysing the long-range correlation with detrended fluctuation analysis. Through a large number of real data collected by the travel time detection system in Beijing, the variation of flow in different time periods and intersections is studied. According to the long-range correlation in different time scales, it mainly discuss the effect of intersection location in road net, people activity customs and special traffic controls on urban traffic flow. As demonstrated by obtained results, the urban traffic flow represents three-phase characters similar to highway traffic. Moreover, compared by the two groups of data obtained before and after the special traffic restrictions (vehicles with special numbered plates only run in a special workday) enforcement, it indicates that the rules not only reduce the flow but also avoid irregular fluctuation. 展开更多
关键词 urban traffic data long-range correlation detrended fluctuation analysis special traffic restriction
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Physical properties of relativistic electron beam during long-range propagation in space plasma environment
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作者 薛碧曦 郝建红 +3 位作者 赵强 张芳 范杰清 董志伟 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第10期283-291,共9页
It is known that ion channel can effectively limit the radial expansion of an artificial electron beam during its longrange propagation in the space plasma environment.Most prior studies discussed the focusing charact... It is known that ion channel can effectively limit the radial expansion of an artificial electron beam during its longrange propagation in the space plasma environment.Most prior studies discussed the focusing characteristics of the beam in the ion channel,but the establishment process and transient properties of the ion channel itself,which also plays a crucial role during the propagation of the relativistic electron beam in the plasma environment,were commonly neglected.In this study,a series of two-dimensional(2D)particle-in-cell simulations is performed and an analytical model of ion channel oscillation is constructed according to the single-particle motion.The results showed that when the beam density is higher than the density of plasma environment,ion channel can be established and always continues to oscillate periodically over the entire propagation.Multiple factors,including the beam electron density,initial beam radius,and the plasma density can affect the oscillation properties of ion channel.Axial velocity of the beam oscillates synchronously with the ion channel and this phenomenon will finally develop into a two-stream instability which can seriously affect the effective transport for relativistic electron beam.Choosing appropriate beam parameters based on various plasma environments may contribute to the improvement of the stability of ion channel.Additionally,radial expansion of the beam can be limited by ion channel and a stable long-range propagation in terrestrial atmosphere may be achieved. 展开更多
关键词 ion channel space plasma environment long-range propagation particle-in-cell(PIC)simulation
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STATISTICAL PROPERTIES OF LONG-RANGE CONTACTS IN GLOBULAR PROTEINS
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作者 王向红 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2004年第2期187-194,共8页
The analysis of residue-residue contacts in protein structures can shed some light on our understanding of the folding and stability of proteins. In this paper, we study the statistical properties of long-range and sh... The analysis of residue-residue contacts in protein structures can shed some light on our understanding of the folding and stability of proteins. In this paper, we study the statistical properties of long-range and short-range residue- residue contacts of 91 globular proteins using CSU software and analyze the importance of long-range contacts in globular protein structure. There are many short-range and long-range contacts in globular proteins, and it is found that the average number of long-range contacts per residue is 5.63 and the percentage of residue-residue contacts which are involved in long- range ones is 59.4%. In more detail, the distribution of long-range contacts in different residue intervals is investigated and it is found that the residues occurring in the interval range of 4-10 residues apart in the sequence contribute more long-range contacts to the stability of globular protein. The number of long-range contacts per residue, which is a measure of ability to form residue-residue contacts, is also calculated for 20 different amino acid residues. It is shown that hydrophobic residues (including Leu, Val, He, Met, Phe, Tyr, Cys and Trp) having a large number of long-range contacts easily form long-range contacts, while the hydrophilic amino acids (including Ala, Gly, Thr, His, Glu, Gln, Asp, Asn, Lys, Ser, Arg, and Pro) form long-range contacts with more difficulty. The relationship between the Fauchere-Pliska hydrophobicity scale (FPH) and the number of short-range and long-range contacts per residue for 20 amino acid residues is also studied. An approximately linear relationship between the Fauchere-Pliska hydrophobicity scale (FPH) and the number of long-range contacts per residue CL, is found and can be expressed as CL = a + b × FPH where a = 5.04 and b = 1.23. These results can help us to understand the role of residue-residue contacts in globular protein structure. 展开更多
关键词 long-range and short-range contact Structural class Globular protein CSU software
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LONG-RANGE CORRELATIONS IN DNA SEQUENCES USING TWO-DIMENSIONAL DNA WALKS
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作者 JinChena Lin-xiZhanga De-luZhaob 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2005年第1期11-16,共6页
The characterization of long-range correlations and fractal properties of DNA sequences has proved to be adifficult though rewarding task mainly due to the mosaic character of DNA consisting of many patches of various... The characterization of long-range correlations and fractal properties of DNA sequences has proved to be adifficult though rewarding task mainly due to the mosaic character of DNA consisting of many patches of various lengthswith different nucleotide constitutions.In this paper we investigate statistical correlations among different positions in DNAsequences using the two-dimensional DNA walk.The root-mean-square fluctuation F(l)is described by a power law.Theautocorrelation function C(l),which is used to measure the linear dependence and periodicity,exists a power law ofC(l)-l^(-μ).We also calculate the mean-square distance<R^2(l)>along the DNA chain,and it may be expressed as<R^2(l)>-l^(?)with 2>γ>1.Our investigations can provide some insights into long-range correlations in DNA sequences. 展开更多
关键词 Autocorrelation function DNA sequence long-range correlation.
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