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Propagation Dynamics of Forced Pulsating Waves for a Time Periodic Lotka-Volterra Cooperative System with Nonlocal Effects in Shifting Habitats
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作者 Zewen Gong 《Journal of Applied Mathematics and Physics》 2024年第10期3402-3421,共20页
In this paper, we will concern the existence, asymptotic behaviors and stability of forced pulsating waves for a Lotka-Volterra cooperative system with nonlocal effects under shifting habitats. By using the alternativ... In this paper, we will concern the existence, asymptotic behaviors and stability of forced pulsating waves for a Lotka-Volterra cooperative system with nonlocal effects under shifting habitats. By using the alternatively-coupling upper-lower solution method, we establish the existence of forced pulsating waves, as long as the shifting speed falls in a finite interval where the endpoints are obtained from KPP-Fisher speeds. The asymptotic behaviors of the forced pulsating waves are derived. Finally, with proper initial, the stability of the forced pulsating waves is studied by the squeezing technique based on the comparison principle. 展开更多
关键词 Nonlocal Effects time Periodic Lotka-Volterra System Forced Pulsating Waves Shifting Habitats
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Time Quanta Present in Simple Quantum Systems
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作者 Stanisław Olszewski 《Journal of Modern Physics》 2021年第7期1005-1011,共7页
Differences of the time periods in two independent quantum systems are examined on a semiclassical level. The systems are the electron in the hydrogen atom and a free-electron particle moving in a one-dimensional pote... Differences of the time periods in two independent quantum systems are examined on a semiclassical level. The systems are the electron in the hydrogen atom and a free-electron particle moving in a one-dimensional potential box, respectively. It is demonstrated that in both systems the relativistic correction to the time interval can be expressed as a multiple of the same quantum of time. The size of the quantum is proportional to the ratio of the Planck’s constant and the rest energy of the electron particle. 展开更多
关键词 time periods of the Electron Oscillations in the Bohr Hydrogen Atom and in a One-Dimensional Potential Box Relativistic Correction to the Difference of the time periods time Quanta
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TIME PERIODIC SOLUTION TO THE COMPRESSIBLE NAVIER-STOKES EQUATIONS IN A PERIODIC DOMAIN 被引量:5
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作者 金春花 杨彤 《Acta Mathematica Scientia》 SCIE CSCD 2016年第4期1015-1029,共15页
This article is concerned with the time periodic solution to the isentropic compressible Navier-Stokes equations in a periodic domain. Using an approach of parabolic regularization, we first obtain the existence of th... This article is concerned with the time periodic solution to the isentropic compressible Navier-Stokes equations in a periodic domain. Using an approach of parabolic regularization, we first obtain the existence of the time periodic solution to a regularized problem under some smallness and symmetry assumptions on the external force. The result for the original compressible Navier-Stokes equations is then obtained by a limiting process. The uniqueness of the periodic solution is also given. 展开更多
关键词 time periodic solution compressible Navier-Stokes equation topology degree energy method
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Travel time prediction with viscoelastic traffic model 被引量:2
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作者 Yongliang ZHANG M.N.SMIRNOVA +2 位作者 A.I.BOGDANOVA Zuojin ZHU N.N.SMIRNOV 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2018年第12期1769-1788,共20页
Travel time through a ring road with a total length of 80 km has been predicted by a viscoelastic traffic model(VEM), which is developed in analogous to the non-Newtonian fluid flow. The VEM expresses a traffic pressu... Travel time through a ring road with a total length of 80 km has been predicted by a viscoelastic traffic model(VEM), which is developed in analogous to the non-Newtonian fluid flow. The VEM expresses a traffic pressure for the unfree flow case by space headway, ensuring that the pressure can be determined by the assumption that the relevant second critical sound speed is exactly equal to the disturbance propagation speed determined by the free flow speed and the braking distance measured by the average vehicular length. The VEM assumes that the sound speed for the free flow case depends on the traffic density in some specific aspects, which ensures that it is exactly identical to the free flow speed on an empty road. To make a comparison, the open Navier-Stokes type model developed by Zhang(ZHANG, H. M. Driver memory, traffic viscosity and a viscous vehicular traffic flow model. Transp. Res. Part B, 37, 27–41(2003)) is adopted to predict the travel time through the ring road for providing the counterpart results.When the traffic free flow speed is 80 km/h, the braking distance is supposed to be 45 m,with the jam density uniquely determined by the average length of vehicles l ≈ 5.8 m. To avoid possible singular points in travel time prediction, a distinguishing period for time averaging is pre-assigned to be 7.5 minutes. It is found that the travel time increases monotonically with the initial traffic density on the ring road. Without ramp effects, for the ring road with the initial density less than the second critical density, the travel time can be simply predicted by using the equilibrium speed. However, this simpler approach is unavailable for scenarios over the second critical. 展开更多
关键词 travel time viscoelastic modeling distinguishing period for time averaging spatial-temporal pattern traffic jam
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Real-time performance of periodic data transmission in EPA industrial Ethernet 被引量:2
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作者 刘宁 仲崇权 莫亚林 《Journal of Beijing Institute of Technology》 EI CAS 2012年第3期336-342,共7页
To evaluate and improve the real-time performance of Ethernet for plant automation(EPA) industrial Ethernet,the real-time performance of EPA periodic data transmission was theoretically and experimentally studied.By... To evaluate and improve the real-time performance of Ethernet for plant automation(EPA) industrial Ethernet,the real-time performance of EPA periodic data transmission was theoretically and experimentally studied.By analyzing information transmission regularity and EPA deterministic scheduling mechanism,periodic messages were categorized as different modes according to their entering-queue time.The scheduling characteristics and delivery time of each mode and their interacting relations were studied,during which the models of real-time performance of periodic information transmission in EPA system were established.On this basis,an experimental platform is developed to test the delivery time of periodic messages transmission in EPA system.According to the analysis and the experiment,the main factors that limit the real-time performance of EPA periodic data transmission and the improvement methods were proposed. 展开更多
关键词 Ethernet for plant automation(EPA) industrial Ethernet periodic data transmission real-time performance delivery time
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Determining the time and space domains forestimating b value in seismic zoning
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作者 黄玮琼 李文香 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第5期3-8,共6页
To take the seismic zone that includes the great shock with M S8.5 as the statistical unit of estimating b value can often lead to more large variance, because the seismogenic zone of the great shock with M... To take the seismic zone that includes the great shock with M S8.5 as the statistical unit of estimating b value can often lead to more large variance, because the seismogenic zone of the great shock with M S8.5 are larger than that delineated in general seismic zone. Two-level statistical units are considered in this paper. The seismic province is the first level unit that is suitable for group of earthquakes including the great shock of M S8.5. A seismic province can be divided into several seismic zones. They can be taken as the second level unit for group of quakes in which the super magnitude of the greatest shock do not exceed 8. Because of the nonstationarity in time of seismic activity, the unbalancedness of data and differential of seismic temporal series feature in different areas need to be considered when we select the time period for estimating b value. According to local conditions, the time period is selected at one′s discretion in order to reflect seismicity level of this statistical unit in future 100 years. 展开更多
关键词 estimating b VALUE statistical unit time period magnitude interval
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Pseudo analytical solution to time periodic stiffness systems
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作者 王延忠 周元子 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期97-102,共6页
An analytical form of state transition matrix for a system of equations with time periodic stiffness is derived in order to solve the free response and also allow for the determination of system stability and bifurcat... An analytical form of state transition matrix for a system of equations with time periodic stiffness is derived in order to solve the free response and also allow for the determination of system stability and bifurcation. A pseudoclosed form complete solution for parametrically excited systems subjected to inhomogeneous generalized forcing is developed, based on the Fourier expansion of periodic matrices and the substitution of matrix exponential terms via Lagrange-Sylvester theorem. A Mathieu type of equation with large amplitude is presented to demonstrate the method of formulating state transition matrix and Floquet multipliers. A two-degree-of-freedom system with irregular time periodic stiffness characterized by spiral bevel gear mesh vibration is presented to find forced response in stability and instability. The obtained results are presented and discussed. 展开更多
关键词 parametric excitation time periodic stiffness STABILITY RESPONSE
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STABILITY OF TIME-PERIODIC TRAVELING FRONTS IN BISTABLE REACTION-ADVECTION-DIFFUSION EQUATIONS
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作者 盛伟杰 《Acta Mathematica Scientia》 SCIE CSCD 2016年第3期802-814,共13页
This paper is concerned with the global exponential stability of time periodic traveling fronts of reaction-advection-diffusion equations with time periodic bistable nonlinearity in infinite cylinders. It is well know... This paper is concerned with the global exponential stability of time periodic traveling fronts of reaction-advection-diffusion equations with time periodic bistable nonlinearity in infinite cylinders. It is well known that such traveling fronts exist and are asymptotically stable. In this paper, we further show that such fronts are globally exponentially stable. The main difficulty is to construct appropriate supersolutions and subsolutions. 展开更多
关键词 STABILITY reaction-advection-diffusion equations BISTABLE time periodic tray- eling fronts
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TIME PERIODIC SOLUTIONS OF NON-ISENTROPIC COMPRESSIBLE MAGNETOHYDRODYNAMIC SYSTEM
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作者 许秋菊 蔡虹 谭忠 《Acta Mathematica Scientia》 SCIE CSCD 2015年第1期216-234,共19页
In this paper, we study the non-isentropic compressible magnetohydrodynamic system with a time periodic external force in R^n. Under the condition that the optimal time decay rates are obtained by spectral analysis, w... In this paper, we study the non-isentropic compressible magnetohydrodynamic system with a time periodic external force in R^n. Under the condition that the optimal time decay rates are obtained by spectral analysis, we show that the existence, uniqueness and time-asymptotic stability of time periodic solutions when the space dimension n 〉 5. Our proof is based on a combination of the energy method and the contraction mapping theorem. 展开更多
关键词 non-isentropic compressible magnetohydrodynamic system time periodic solution optimal time decay rates energy estimates
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EXISTENCE OF TIME PERIODIC SOLUTIONS FOR A DAMPED GENERALIZED COUPLED NONLINEAR WAVE EQUATIONS
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作者 房少梅 郭柏灵 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第6期673-683,共11页
The time periodic solution problem of damped generalized coupled nonlinear wave equations with periodic boundary condition was studied. By using the Galerkin method to construct the approximating sequence of time peri... The time periodic solution problem of damped generalized coupled nonlinear wave equations with periodic boundary condition was studied. By using the Galerkin method to construct the approximating sequence of time periodic solutions, a priori estimate and Laray_Schauder fixed point theorem to prove the convergence of the approximate solutions, the existence of time periodic solutions for a damped generalized coupled nonlinear wave equations can be obtained. 展开更多
关键词 nonlinear wave equations priori estimate time periodic solution
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Study of the effects on GPS coordinate time series caused by higher-order ionospheric corrections calculated using the DIPOLE model
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作者 Liansheng Deng Weiping Jiang +2 位作者 Hua Chen Zhaohan Zhu Wen Zhao 《Geodesy and Geodynamics》 2017年第2期111-119,共9页
As one of the main error sources in high-precision Global Positioning System (GPS) data processing, higher-order ionospheric (HOI) delays cause significant effects on coordinate time series that cannot be ignored ... As one of the main error sources in high-precision Global Positioning System (GPS) data processing, higher-order ionospheric (HOI) delays cause significant effects on coordinate time series that cannot be ignored in analyses of long time series. Typically two geomagnetic models, DIPOLE model and Inter- national Geomagnetic Reference Field (IGRF) model, are used for calculating HOI corrections. This paper investigates the effects of HOI correction caused by the DIPOLE model on coordinate time series. GPS data from 104 globally distributed International GNSS Service (IGS) stations spanning from January, 1999 to December, 2003 were reprocessed following up-to-date processing strategies utilizing GAMIT and GLOBK software. Two coordinate time series solutions before and after applying HOI corrections using the DIPOLE model were derived for studying the effects in terms of seasonal variations and noise amplitudes. The results show that after applying the HOI corrections calculated with DIPOLE, the noise amplitudes of the coordinate time series increased, especially in the north and east directions, and the increased amplitudes of the flicker noise were larger than those of the white noise. Furthermore, spurious periodic signals that were probably introduced by the HOI corrections from the DIPOLE model were also found. Moreover, an apparent increase was confirmed for the power spectra of most of the stations, especially in the north direction, and the amplitudes of both the annual and semi-annual signals also increased in the north and east directions. It can be inferred that the quality of the external data sources such as the geomagnetic model might be the key factors that lead to the above results. The results also suggest that we should be very careful when the DIPOLE model is used for HOI corrections. 展开更多
关键词 FHigher-order ionospheric corrections Coordinate time series Periodic characteristics Noise amplitudes
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Comparative Study of foF2 during Quiet Geomagnetic Activity with URSI and CCIR Predictions during the Phase Minimum of Solar Cycle 22
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作者 Moustapha Konaté Abidina Diabaté +2 位作者 Kadidia Nonlo Drabo Emmanuel Nanéma Frédéric Ouattara 《Journal of Applied Mathematics and Physics》 2022年第12期3562-3571,共10页
This paper investigates the performance of the latest International Reference Ionosphere model to predict the critical frequency at low latitudes in the African region. The variability of the critical frequency of the... This paper investigates the performance of the latest International Reference Ionosphere model to predict the critical frequency at low latitudes in the African region. The variability of the critical frequency of the F2 layer of the ionosphere (foF2) is studied for the different seasons of the phase minimum of solar cycle 22 during quiet geomagnetic activity at the Ouagadougou station. The data used are those provided by the ionosonde and the predictions of the two subprograms: International Radio Consultative Committee (CCIR) and International Radio-Scientific Union (URSI) of the 2016 version of the International Reference Ionosphere model. This study shows that, in general, URSI and CCIR of the IRI-2016 model are able to reproduce fairly well the variability of the critical frequency of the F2 layer of the ionosphere at low latitudes during the phase minimum at the Ouagadougou station. However, the model shows an almost homogeneous overestimation of the foF2 during the four seasons studied. The good response is observed between 0700 TL and 1900 TL for the available data. The agreement between the subroutine responses and the observed results is between reasonable and poor. The best match state response is obtained in winter with the CCIR subroutine. These results show that there is a need to improve both CCIR and URSI subroutines of the IRI-2016 model in low latitudes in the African region. 展开更多
关键词 FOF2 IRI IONOSONDE Quiet time periods Solar Cycle Phase Minimum
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Viruses and autism: A Bi-mutual cause and effect
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作者 Mohammed Al-Beltagi Nermin Kamal Saeed +3 位作者 Reem Elbeltagi Adel Salah Bediwy Syed A Saboor Aftab Rawan Alhawamdeh 《World Journal of Virology》 2023年第3期172-192,共21页
Autism spectrum disorder(ASD)is a group of heterogeneous,multi-factorial,neurodevelopmental disorders resulting from genetic and environmental factors interplay.Infection is a significant trigger of autism,especially ... Autism spectrum disorder(ASD)is a group of heterogeneous,multi-factorial,neurodevelopmental disorders resulting from genetic and environmental factors interplay.Infection is a significant trigger of autism,especially during the critical developmental period.There is a strong interplay between the viral infection as a trigger and a result of ASD.We aim to highlight the mutual relationship between autism and viruses.We performed a thorough literature review and included 158 research in this review.Most of the literature agreed on the possible effects of the viral infection during the critical period of development on the risk of developing autism,especially for specific viral infections such as Rubella,Cytomegalovirus,Herpes Simplex virus,Varicella Zoster Virus,Influenza virus,Zika virus,and severe acute respiratory syndrome coronavirus 2.Viral infection directly infects the brain,triggers immune activation,induces epigenetic changes,and raises the risks of having a child with autism.At the same time,there is some evidence of increased risk of infection,including viral infections in children with autism,due to lots of factors.There is an increased risk of developing autism with a specific viral infection during the early developmental period and an increased risk of viral infections in children with autism.In addition,children with autism are at increased risk of infection,including viruses.Every effort should be made to prevent maternal and early-life infections and reduce the risk of autism.Immune modulation of children with autism should be considered to reduce the risk of infection. 展开更多
关键词 AUTISM Children Rubella Cytomegalovirus Herpes simplex virus Influenza virus Zika virus SARS-CoV-2 COVID-19 Viral infection Core Tip:There is a mutual relationship between viral infections and autism.There is an increased risk of developing autism when contracting a viral infection during pregnancy or early postnatal life during the critical period of brain development.At the same time children with autism have many co-morbidities that expose them to more risk of contracting infections including viruses.Therefore every effort should be made to prevent infections especially during this critical period of neurodevelopment.Parents should also be educated about the importance of vaccination and immune modulation in children with autism to avoid further infections.
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Existence and asymptotic estimates of periodic solutions of El Nio mechanism of atmospheric physics 被引量:1
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作者 李晓静 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第2期9-12,共4页
This paper is devoted to studying the El Nino mechanism of atmospheric physics. The existence and asymptotic estimates of periodic solutions for its model are obtained by employing the technique of upper and lower sol... This paper is devoted to studying the El Nino mechanism of atmospheric physics. The existence and asymptotic estimates of periodic solutions for its model are obtained by employing the technique of upper and lower solution, and using the continuation theorem of coincidence degree theory. 展开更多
关键词 nonlinear time delay El Nino phenomenon periodic solution
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A tectonic stress map of China and adjacent regions from earthquakes occurred during 2000~2004
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作者 郑中华 陈永顺 《Acta Seismologica Sinica(English Edition)》 CSCD 2006年第3期344-349,共6页
Earthquake focal mechanism solutions provide the basic information about the present-day regional tectonics stress distribution, which controls the activities of crustal faults. Therefore, continued efforts for updati... Earthquake focal mechanism solutions provide the basic information about the present-day regional tectonics stress distribution, which controls the activities of crustal faults. Therefore, continued efforts for updating the database of earthquake focal mechanism solutions are quite valuable and important. 展开更多
关键词 tectonic stress map earthquake focal mechanism solutions short time period deep earthquake
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Spreading Speed for a Periodic Reaction-diffusion Model with Nonmonotone Birth Function
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作者 HUANG Ye-hui WENG Pei-xuan 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第3期467-474,共8页
A reaction-diffusion model for a single species with age structure and nonlocal reaction for periodic time t is derived. Some results about the model with monotone birth function are firstly introduced, and then by co... A reaction-diffusion model for a single species with age structure and nonlocal reaction for periodic time t is derived. Some results about the model with monotone birth function are firstly introduced, and then by constructing two auxiliary equations and squeezing method, the spreading speed for the system with nonmonotone birth function is obtained. 展开更多
关键词 spreading speed nonmonotone birth function period time age structure nonlocal reaction
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The Underground Water Level Simulation in Imamzadeh Jafar Plateau by the Use of Mudflow Software
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作者 Arash Rostami Rahim Ali Mohammadi Nafchi 《Open Journal of Geology》 2016年第8期852-858,共8页
The most secure method in providing water in the dry and semi-dry regions is the use of underground water sources and due to over consumption of water aquifers capacities, most of fields and specially Imamzadeh Jafar ... The most secure method in providing water in the dry and semi-dry regions is the use of underground water sources and due to over consumption of water aquifers capacities, most of fields and specially Imamzadeh Jafar are faced with negative performance and balance, which threatens the land subsiding. The plateau with the annual raining of 438 millimeters has 169 deep and semi-deep wells with annual 36.68 million consumption and this issue has increased the research signification, in order to protect and relive the required water aquifers, there is a need to predict the underground water level accurately in different condition. In this research, by the use of balance equation and modflow software in Imamzadeh Jafar, water aquifer was analyzed within seven scenario. The underground water level evaluation for the short run periods for 2 years and middle term of 4 years and 12 years of long term was performed;and the results showed that the performance and balance of the plateau was increased due to increase of water consumption compared to the water aquifer quantity in the region that was negative. To the point that the 1, 3, 4, 5, 7 scenarios (minimum 0.17 and maximum -11.34) and 2, 6 scenarios in different timely periods show that the underground water saving volume is positive (minimum 3.64 and maximum 19.83). 展开更多
关键词 Water Balance Equation MODFLOW Short Run timely periods Medium Run timely periods Long Run timely periods Underground Water
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Rediscussion on the seismic regime network
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作者 王泽皋 孙佩卿 +3 位作者 高景春 李淑莲 张雪 郭妍 《Acta Seismologica Sinica(English Edition)》 CSCD 1994年第3期369-377,共9页
On the basis of the past research and utilization on the windows and belts of seismic regime, the seismic regime network which has been supposed and proved in the past is set up by using the monthly frequency data of ... On the basis of the past research and utilization on the windows and belts of seismic regime, the seismic regime network which has been supposed and proved in the past is set up by using the monthly frequency data of small earthquakes from 1970 to 1991 over the whole country. Through checking its function in practice, it is found that the spatial distribution of precursor information is not an isolate window or belt, but a broad precursor information field before the Ms≥7. 0 earthquakes in China and its nearby regions. According to the windows and belts in the field, synchronism and generality of initial time and place of prediction, the comprehensive prediction of activity time periods of groups of strong earthquakes and the detail method of correspondence of groups are proposed. After restrict mathematical test, 10 prediction methods for references are set forth, in which two best methods are selected as references for the whole case prediction in one to three years. Some related problems are discussed at the end of this paper. 展开更多
关键词 seismic regime network seismic precursor information field comprehensive prediction period of activity time
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Long-term optical flux and colour variability in quasars
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作者 N.Sukanya C.S.Stalin +3 位作者 S.Jeyakumar D.Praveen Amab Dhani R.Damle 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第2期63-68,共6页
We have used optical V and R band observations from the Massive Compact Halo Object (MACHO) project on a sample of 59 quasars behind the Magellanic clouds to study their long term optical flux and colour variations.... We have used optical V and R band observations from the Massive Compact Halo Object (MACHO) project on a sample of 59 quasars behind the Magellanic clouds to study their long term optical flux and colour variations. These quasars, lying in the redshift range of 0.2 〈 z 〈 2.8 and having apparent V band magnitudes between 16.6 and 20.1 mag, have observations ranging from 49 to 1353 epochs span- ning over 7.5 yr with frequency of sampling between 2 to 10 days. All the quasars show variability during the observing period. The normalised excess variance (Fvar) in V and R bands are in the range 0.2% 〈 F^r 〈 1.6% and 0.1% 〈 Fnr 〈 1.5% respectively. In a large fraction of the sources, Fvar is larger in the V band compared to the R band. From the z-transformed discrete cross-correlation function analysis, we find that there is no lag between the V and R band variations. Adopting the Markov Chain Monte Carlo (MCMC) approach, and properly taking into account the correlation between the errors in colours and mag- nitudes, it is found that the majority of sources show a bluer when brighter trend, while a minor fraction of quasars show the opposite behaviour. This is similar to the results obtained from another two independent algorithms, namely the weighted linear least squares fit (FITEXY) and the bivariate correlated errors and intrinsic scatter regression (BCES). However, the ordinary least squares (OLS) fit, normally used in the colour variability studies of quasars, indicates that all the quasars studied here show a bluer when brighter trend. It is therefore very clear that the OLS algorithm cannot be used for the study of colour variability in quasars. 展开更多
关键词 time lag -- periodicity -- active galaxies -- quasars
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Effect of sublethal doses of the insecticide imidacloprid on adaptive traits of Drosophila melanogaster:Response to treatment over and after 15 consecutive generations
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作者 Thais de Franca Patarro Antonio Jose Manzato +1 位作者 Lilian Madi-Ravazzi Hermione E.M.de Campos Bicudo 《Open Journal of Animal Sciences》 2013年第4期8-19,共12页
A sublethal dose of Imidacloprid, considered actually as the most widely used insecticide against biting and sucking insects, was administered to Drosophila melanogaster for detecting effects on biological traits. The... A sublethal dose of Imidacloprid, considered actually as the most widely used insecticide against biting and sucking insects, was administered to Drosophila melanogaster for detecting effects on biological traits. The choice of this species as organism-model potentially opens the possibility to explore more deeply the processes involved in those effects because, among other reasons, there is a large accumulation of biological knowledge on this species and because it propitiates multiple approaches in laboratory and nature. The flies were treated along 15 consecutive generations. F1 parents were randomly taken among virgin flies from the stocks, but the parents of the successive generations were the first 15 couples emerged in the previous one. The number of progeny (productivity) and the duration of the emergence period were analyzed in every generation revealing insecticide toxicity in 12 of the 15 generations. The observation of an increase in the number of progeny over the generations, which occurred in both control and treated experiments (although maintaining higher productivity in the control), suggested an effect of the use of the first 15 emerged couples in successive generations. A comparative analysis of the mortality of the F15 adult flies exposed to imidacloprid by contact, which involved flies from the control, treatment and from the stocks that originated the experiments, reinforced this idea, indicating a genetic interplay of the emergence speed with productivity and adult tolerance to the insecticide, a subject that may be better explored in another study. Toxicity was also observed for the traits longevity, viability during development from egg to adult and oviposition rate. Considering the present intensive use of imidacloprid, the harmful effects observed in these important biological characteristics may be considered able to decrease the adaptive value of D. melanogaster populations exposing them at risk of decline. 展开更多
关键词 Productivity LONGEVITY Emergence time Period Egg-Adult Viability OVIPOSITION Tolerance
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