摘要:
We introduce the variant rate and white noise into the susceptible-infected-removed (SIR) model for epidemics, discuss the epidemic dynamics of a multiple-compartment system, and describe this system by using master equations. For both the local epidemic spreading system and the whole multiple-compartment system, we find that a threshold could be useful in forecasting when the epidemic vanishes. Furthermore, numerical simulations show that a model with the variant infection rate and white noise can improve fitting with real SARS data.
作者机构:
[Kechechyan, A.; Kizka, V.; Agakishiev, G.; Averichev, G. S.; Bunzarov, I.; Efimov, L. G.; Panebratsev, Y.; Alakhverdyants, A. V.; Shahaliev, E.; Rogachevskiy, O. V.; Fedorisin, J.; Zoulkarneeva, Y.; Tokarev, M.; Filip, P.; Lednicky, R.; Dedovich, T. G.; Vokal, S.] Joint Inst Nucl Res, Dubna 141980, Russia.;[Underwood, D. G.; Krueger, K.; Bridgeman, A.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Jones, P. G.; Nelson, J. M.; Barnby, L. S.] Univ Birmingham, Birmingham, W Midlands, England.;[Ullrich, T.; Pile, P.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Longacre, R. S.; Webb, J. C.; Sorensen, P.; Christie, W.; Arkhipkin, D.; Debbe, R. R.; Lebedev, A.; Burton, T. P.; Dunlop, J. C.; Gordon, A.; Landgraf, J. M.; Yip, K.; Didenko, L.; Guryn, W.; Mitrovski, M. K.; Van Buren, G.; Lee, J. H.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Mall, O. I.; Draper, J. E.; Cebra, D.; Brovko, S. G.; Sangaline, E.; Reed, R.; de la Barca Sanchez, M. Calderon; Romero, J. L.; Salur, S.; Haag, B.; Liu, H.] Univ Calif Davis, Davis, CA 95616 USA.
通讯机构:
[Agakishiev, G.] J;Joint Inst Nucl Res, Dubna 141980, Russia.
作者:
Agakishiev, G.*;Aggarwal, M. M.;Ahammed, Z.;Alakhverdyants, A. V.;Alekseev, I.;...
期刊:
PHYSICAL REVIEW C,2012年86(1) ISSN:2469-9985
通讯作者:
Agakishiev, G.
作者机构:
[Kechechyan, A.; Kizka, V.; Agakishiev, G.; Averichev, G. S.; Bunzarov, I.; Efimov, L. G.; Panebratsev, Y.; Alakhverdyants, A. V.; Shahaliev, E.; Rogachevskiy, O. V.; Fedorisin, J.; Zoulkarneeva, Y.; Tokarev, M.; Filip, P.; Lednicky, R.; Dedovich, T. G.; Vokal, S.] Joint Inst Nucl Res, Dubna 141980, Russia.;[Underwood, D. G.; Krueger, K.; Bridgeman, A.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Ullrich, T.; Pile, P.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Longacre, R. S.; Webb, J. C.; Sorensen, P.; Christie, W.; Arkhipkin, D.; Debbe, R. R.; Lebedev, A.; Burton, T. P.; Dunlop, J. C.; Gordon, A.; Landgraf, J. M.; Yip, K.; Didenko, L.; Guryn, W.; Mitrovski, M. K.; Van Buren, G.; Lee, J. H.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Perkins, C.; Crawford, H. J.; Engelage, J.; Judd, E. G.] Univ Calif Berkeley, Berkeley, CA 94720 USA.;[Sanchez, M. Calderon de la Barca; Mall, O. I.; Draper, J. E.; Cebra, D.; Brovko, S. G.; Sangaline, E.; Reed, R.; Romero, J. L.; Salur, S.; Haag, B.; Liu, H.] Univ Calif Davis, Davis, CA 95616 USA.
通讯机构:
[Agakishiev, G.] J;Joint Inst Nucl Res, Dubna 141980, Russia.
摘要:
We present STAR measurements of azimuthal anisotropy by means of the two- and four-particle cumulants nu(2) (nu(2){2} and nu(2){4}) for Au + Au and Cu + Cu collisions at center-of-mass energies root S-NN = 62.4 and 200 GeV. The difference between nu(2){2}(2) and nu(2){4}(2) is related to nu(2) fluctuations (sigma(nu 2)) and nonflow (delta(2)). We present an upper limit to sigma(nu 2)/nu 2. Following the assumption that eccentricity fluctuations sigma(epsilon) dominate nu(2) fluctuations nu(2)/sigma nu(2) approximate to epsilon/sigma epsilon we deduce the nonflow implied for several models of eccentricity fluctuations that would be required for consistency with nu(2){2} and nu(2){4}. We also present results on the ratio of nu(2) to eccentricity.
作者:
Agakishiev, G.*;Aggarwal, M. M.;Ahammed, Z.;Alakhverdyants, A. V.;Alekseev, I.;...
期刊:
PHYSICAL REVIEW C,2012年86(6) ISSN:2469-9985
通讯作者:
Agakishiev, G.
作者机构:
[Kechechyan, A.; Kizka, V.; Agakishiev, G.; Averichev, G. S.; Bunzarov, I.; Efimov, L. G.; Panebratsev, Y.; Alakhverdyants, A. V.; Shahaliev, E.; Rogachevskiy, O. V.; Fedorisin, J.; Zoulkarneeva, Y.; Tokarev, M.; Filip, P.; Lednicky, R.; Dedovich, T. G.; Vokal, S.] Joint Inst Nucl Res, Dubna 141980, Russia.;[Underwood, D. G.; Krueger, K.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Ullrich, T.; Pile, P.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Longacre, R. S.; Webb, J. C.; Sorensen, P.; Christie, W.; Arkhipkin, D.; Debbe, R. R.; Lebedev, A.; Burton, T. P.; Dunlop, J. C.; Gordon, A.; Landgraf, J. M.; Yip, K.; Didenko, L.; Mitrovski, M. K.; Van Buren, G.; Lee, J. H.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Perkins, C.; Crawford, H. J.; Engelage, J.; Judd, E. G.] Univ Calif Berkeley, Berkeley, CA 94720 USA.;[Sanchez, M. Calderon de la Barca; Mall, O. I.; Draper, J. E.; Cebra, D.; Brovko, S. G.; Sangaline, E.; Reed, R.; Romero, J. L.; Salur, S.; Haag, B.] Univ Calif Davis, Davis, CA 95616 USA.
通讯机构:
[Agakishiev, G.] J;Joint Inst Nucl Res, Dubna 141980, Russia.
摘要:
We present two-dimensional (2D) two-particle angular correlations measured with the STAR detector on relative pseudorapidity eta and azimuth phi for charged particles from Au-Au collisions at root s(NN) = 62 and 200 GeV with transverse momentum p(t) >= 0.15 GeV/c, vertical bar eta vertical bar <= 1, and 2 pi in azimuth. Observed correlations include a same-side (relative azimuth <pi/2) 2D peak, a closely related away-side azimuth dipole, and an azimuth quadrupole conventionally associated with elliptic flow. The same-side 2D peak and away-side dipole are explained by semihard parton scattering and fragmentation (minijets) in proton-proton and peripheral nucleus-nucleus collisions. Those structures follow N-N binary-collision scaling in Au-Au collisions until midcentrality, where a transition to a qualitatively different centrality trend occurs within one 10% centrality bin. Above the transition point the number of same-side and away-side correlated pairs increases rapidly relative to binary-collision scaling, the eta width of the same-side 2D peak also increases rapidly (eta elongation), and the phi width actually decreases significantly. Those centrality trends are in marked contrast with conventional expectations for jet quenching in a dense medium. The observed centrality trends are compared to perturbative QCD predictions computed in HIJING, which serve as a theoretical baseline, and to the expected trends for semihard parton scattering and fragmentation in a thermalized opaque medium predicted by theoretical calculations and phenomenological models. We are unable to reconcile a semihard parton scattering and fragmentation origin for the observed correlation structure and centrality trends with heavy-ion collision scenarios that invoke rapid parton thermalization. If the collision system turns out to be effectively opaque to few-GeV partons the present observations would be inconsistent with the minijet picture discussed here. DOI: 10.1103/PhysRevC.86.064902
摘要:
Recently, wireless sensor networks have been used in many promising applications including military surveillance, wildlife tracking, habitat monitoring and so on. They are an indispensable requirement for a sensor node to be able to find its own location. Many range-free estimate approaches eliminate the need of high-cost specialised hardware, at the cost of a less accurate localisation. In addition, the radio propagation characteristics vary over time and are environment dependent, thus imposing high calibration costs for the range-free localisation schemes. In order to reconcile the need for the high accuracy in location estimation, we describe, design, implement and evaluate a novel localisation scheme called laser beam scan localisation (BLS) by combining grid and light (laser) with mobile localisation policy for wireless sensor networks. The scheme utilises a moving location assistant (LA) with a laser beam, through which the deployed area is scanned and Zigbee platform is adopted for experiments in this article. The LA sends IDs to unknown nodes to obtain the locations of sensor nodes. High localisation accuracy can be achieved without the aid of expensive hardware on the sensor nodes, as required by other localisation systems. The scheme yields significant benefits compared with other localisation methods. First, BLS is a distributed and localised scheme, and the LA broadcasts IDs while unknown nodes listen passively. No interactive intersensor communications are involved in this process; thus, sensor energy is saved. Second, BLS reaches a sub-metre localisation error. Third, because the equation is simple, computational cost is low. Finally, BLS is a low-cost scheme because it does not require any infrastructure or additional hardware for sensor nodes.
作者机构:
[Gao Zong-Mao; Gu Jiao; Li Wei] Huazhong Normal Univ, Complex Sci Ctr, Wuhan 430079, Peoples R China.;[Gao Zong-Mao; Gu Jiao; Li Wei] Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.;[Gu Jiao; Li Wei] Max Planck Inst Math Sci, Leipzig, Germany.
通讯机构:
[Li Wei] H;Huazhong Normal Univ, Complex Sci Ctr, Wuhan 430079, Peoples R China.
作者机构:
[Li Wei] Cent China Normal Univ, Complex Sci Ctr, Wuhan 430079, Peoples R China.;[Li Wei] Max Planck Inst Math Sci, D-04103 Leipzig, Germany.;[Luo Yang; Wang YuanFang; Cai AiPing] Cent China Normal Univ, Coll Phys Sci & Technol, Wuhan 430079, Peoples R China.;[Luo Yang] Fudan Univ, Sch Math Sci, Shanghai 200433, Peoples R China.
通讯机构:
[Li Wei] C;Cent China Normal Univ, Complex Sci Ctr, Wuhan 430079, Peoples R China.
作者:
Agakishiev, H.*;Aggarwal, M. M.;Ahammed, Z.;Alakhverdyants, A. V.;Alekseev, I.;...
期刊:
Nature,2011年473(7347):353-356 ISSN:0028-0836
通讯作者:
Agakishiev, H.
作者机构:
[Kechechyan, A.; Kizka, V.; Agakishiev, H.; Averichev, G. S.; Bunzarov, I.; Efimov, L. G.; Panebratsev, Y.; Alakhverdyants, A. V.; Shahaliev, E.; Rogachevskiy, O. V.; Fedorisin, J.; Zoulkarneev, R.; Zoulkarneeva, Y.; Tokarev, M.; Filip, P.; Lednicky, R.; Dedovich, T. G.; Vokal, S.] Joint Inst Nucl Res, Dubna 141980, Russia.;[Bhati, A. K.; K. Pruthi, N.; Aggarwal, M. M.] Panjab Univ, Chandigarh 160014, India.;[Sakrejda, I.; Wieman, H.; Masui, H.; Schmah, A. M.; Porter, J.; Sichtermann, E. P.; Naglis, M.; Grebenyuk, O. G.; Sun, X. M.; Ploskon, M. A.; Thomas, J. H.; Poskanzer, A. M.; Ritter, H. G.; Zhang, Y.; Powell, C. B.; Hjort, E.; Jacobs, P.; Kiryluk, J.; Klein, S. R.; Olson, D.; Odyniec, G.; Matis, H. S.; Symons, T. J. M.; Ahammed, Z.; Dong, X.] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA.;[Koroleva, L.; Svirida, D. N.; Morozov, B.; Bordyuzhin, I. G.; Alekseev, I.] Alikhanov Inst Theoret & Expt Phys, Moscow 117218, Russia.;[Joseph, J.; Vanfossen, J. A., Jr.; Pandit, Y.; Zhang, W. M.; Kumar, L.; Anderson, B. D.; Margetis, S.; Alford, J.; Keane, D.; Bouchet, J.; Subba, N. L.] Kent State Univ, Kent, OH 44242 USA.
通讯机构:
Joint Institute for Nuclear Research, Russian Federation
摘要:
High-energy nuclear collisions create an energy density similar to that of the Universe microseconds after the Big Bang(1); in both cases, matter and antimatter are formed with comparable abundance. However, the relatively short-lived expansion in nuclear collisions allows antimatter to decouple quickly from matter, and avoid annihilation. Thus, a high-energy accelerator of heavy nuclei provides an efficient means of producing and studying antimatter. The antimatter helium-4 nucleus ((4)(He) over bar), also known as the anti-alpha ((alpha) over bar), consists of two antiprotons and two antineutrons (baryon number B = -4). It has not been observed previously, although the alpha-particle was identified a century ago by Rutherford and is present in cosmic radiation at the ten per cent level(2). Antimatter nuclei with B -1 have been observed only as rare products of interactions at particle accelerators, where the rate of antinucleus production in high-energy collisions decreases by a factor of about 1,000 with each additional antinucleon(3-5). Here we report the observation of (4)<(He) over bar, the heaviest observed antinucleus to date. In total, 18 (4)(He) over bar counts were detected at the STAR experiment at the Relativistic Heavy Ion Collider (RHIC; ref. 6) in 10(9) recorded gold-on-gold (Au+Au) collisions at centre-of-mass energies of 200 GeV and 62 GeV per nucleon-nucleon pair. The yield is consistent with expectations from thermodynamic(7) and coalescent nucleosynthesis(8) models, providing an indication of the production rate of even heavier antimatter nuclei and a benchmark for possible future observations of (4)(He) over bar in cosmic radiation.
关键词:
public transport network;complex network;power-law distribution;small-world
摘要:
We analyze the statistical properties of the urban public bus networks of two cities (Beijing and Chengdu) in China. To this end, we present a comprehensive survey of the degree distribution, average path length, and clustering of both networks. It is shown that both networks exhibit small world behavior and are hierarchically organized. We also discuss the differences between the statistical properties displayed by the two networks. In addition, we propose a weight distribution approach to study the passenger flow through the public bus networks we considered. A hierarchical structure is observed here also.
作者机构:
[Pruthi, N. K.; Bhati, A. K.; Aggarwal, M. M.] Panjab Univ, Chandigarh 160014, India.;[Underwood, D. G.; Krueger, K.; Bridgeman, A.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Ullrich, T.; Pile, P.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Fine, V.; Fisyak, Y.; Videbk, F.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Longacre, R. S.; Webb, J. C.; Sorensen, P.; Christie, W.; Arkhipkin, D.; Debbe, R. R.; Lebedev, A.; Burton, T. P.; Dunlop, J. C.; Gordon, A.; Landgraf, J. M.; Love, W. A.; Yip, K.; Didenko, L.; Guryn, W.; Van Buren, G.; Lee, J. H.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Perkins, C.; Crawford, H. J.; Engelage, J.; Judd, E. G.; Ng, M. J.] Univ Calif Berkeley, Berkeley, CA 94720 USA.;[Mall, O. I.; Draper, J. E.; Cebra, D.; Brovko, S. G.; Sangaline, E.; Reed, R.; de la Barca Sanchez, M. Calderon; Romero, J. L.; Salur, S.; Haag, B.; Liu, H.] Univ Calif Davis, Davis, CA 95616 USA.
通讯机构:
[Aggarwal, M. M.] P;Panjab Univ, Chandigarh 160014, India.
作者:
Aggarwal, M. M.*;Ahammed, Z.;Alakhverdyants, A. V.;Alekseev, I.;Alford, J.;...
期刊:
PHYSICAL REVIEW C,2011年83(2) ISSN:2469-9985
通讯作者:
Aggarwal, M. M.
作者机构:
[Pruthi, N. K.; Bhati, A. K.; Aggarwal, M. M.] Panjab Univ, Chandigarh 160014, India.;[Underwood, D. G.; Krueger, K.; Bridgeman, A.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Ullrich, T.; Pile, P.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Longacre, R. S.; Webb, J. C.; Sorensen, P.; Christie, W.; Arkhipkin, D.; Debbe, R. R.; Lebedev, A.; Burton, T. P.; Dunlop, J. C.; Gordon, A.; Landgraf, J. M.; Tlusty, D.; Love, W. A.; Yip, K.; Didenko, L.; Guryn, W.; Van Buren, G.; Lee, J. H.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Perkins, C.; Crawford, H. J.; Engelage, J.; Judd, E. G.; Ng, M. J.] Univ Calif Berkeley, Berkeley, CA 94720 USA.;[Sanchez, M. Calderon de la Barca; Mall, O. I.; Draper, J. E.; Cebra, D.; Brovko, S. G.; Sangaline, E.; Reed, R.; Romero, J. L.; Salur, S.; Haag, B.; Liu, H.] Univ Calif Davis, Davis, CA 95616 USA.
通讯机构:
[Aggarwal, M. M.] P;Panjab Univ, Chandigarh 160014, India.
摘要:
We present results on strange and multistrange particle production in Au + Au collisions at root s(NN) = 62.4 GeV as measured with the STAR detector at RHIC. Midrapidity transverse momentum spectra and integrated yields of K-S(0), Lambda, Xi, and Omega and their antiparticles are presented for different centrality classes. The particle yields and ratios follow a smooth energy dependence. Chemical freeze-out parameters, temperature, baryon chemical potential, and strangeness saturation factor obtained from the particle yields are presented. Intermediate transverse momentum (p(T)) phenomena are discussed based on the ratio of the measured baryon-to-meson spectra and nuclear modification factor. The centrality dependence of various measurements presented show a similar behavior as seen in Au + Au collisions at root s(NN) = 200 GeV.
作者机构:
[Zheng Liang; Li Wei] Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.;[Zheng Liang; Li Wei] Cent China Normal Univ, Complex Sci Ctr, Wuhan 430079, Peoples R China.;[Li Wei] Max Planck Inst Math Sci, D-04103 Leipzig, Germany.
通讯机构:
[Li Wei] C;Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.
关键词:
finite system;energy nonextensivity;first-principles method;canonical distribution function
摘要:
A first-principles derivation is presented of canonical distributions for a finite thermostat taking into account nonextensive energy. Parameterizing this energy by λ , we derive an explicit form for the distribution functions by regulating λ , and then explore the nontrivial relationship between these functions and energy nonextensivity, as well other system parameters such as system size. A variational entropy function is also derived from these distribution functions.
作者机构:
[Gu Jiao; Li Wei] Max Planck Inst Math Sci, D-04103 Leipzig, Germany.;[Gao ZongMao] Cent China Normal Univ, Coll Phys Sci & Technol, Wuhan 430079, Peoples R China.;[Li Wei] Cent China Normal Univ, Inst Particle Phys, Complex Sci Ctr, Wuhan 430079, Peoples R China.
摘要:
Motivated by the need to include the different characteristics of individuals and the damping effect in predictions of epidemic spreading, we build a model with variant coefficients and white Gaussian noise based on the traditional SIR model. The analytic and simulation results predicted by the model are presented and discussed. The simulations show that using the variant coefficients results in a higher percentage of susceptible individuals and a lower percentage of removed individuals. When the noise is included in the model, the percentage of infected individuals has a wider peak and more fluctuations than that predicted using the traditional SIR model.
作者机构:
[Deng WeiBing; Wang, Qiuping Alexandre] LUNAM Univ, ISMANS, Lab Phys Stat & Syst Complexes, F-72000 Le Mans, France.;[Deng WeiBing; Wang DuJuan; Li Wei] Cent China Normal Univ, Inst Particle Phys, Complex Sci Ctr, Wuhan 430079, Peoples R China.;[Deng WeiBing; Wang, Qiuping Alexandre] Univ Maine, LUNAM Univ, CNRS, UMR 6087,LPEC, F-72085 Le Mans, France.;[Li Wei] Max Planck Inst Math Sci, D-04103 Leipzig, Germany.;[Deng WeiBing] LUNAM Univ, ISMANS, Lab Phys Stat & Syst Complexes, 44 Ave Bartholdi, F-72000 Le Mans, France.
通讯机构:
[Deng WeiBing] L;LUNAM Univ, ISMANS, Lab Phys Stat & Syst Complexes, 44 Ave Bartholdi, F-72000 Le Mans, France.
关键词:
language time series;self-similarity;Hurst exponent;long range correlation;intermittency
摘要:
English and Chinese language frequency time series (LFTS) were constructed based on an English and two Chinese novels. Methods of statistical hypothesis testing were adopted to test the nonlinear properties of the LFTS. Results suggest the series exhibited non-normal, auto-correlative, and stationary characteristics. Moreover, we found that LFTS follow the power law distributions, and thereby we investigated the fractal structure, long range correlation, and intermittency, which indicated the self-similarity features of LFTS, and also provided hints that human societies are likely to share some universal properties.
作者机构:
Argonne National Laboratory, Argonne, IL 60439, United States;Brookhaven National Laboratory, Upton, NY 11973, United States;University of California, Berkeley, CA 94720, United States;University of California, Davis, CA 95616, United States;University of California, Los Angeles, CA 90095, United States
通讯机构:
Joint Institute for Nuclear Research, Russian Federation