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基于ELES模型和CD效用函数的“纵横双向”消费结构变动研究
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作者 阮敬 王兴玉 《湘潭大学学报(哲学社会科学版)》 CSSCI 北大核心 2024年第4期97-103,共7页
探究消费升级对于促进共同富裕具有深远意义。基于CFPS 2010—2020年数据,结合扩展线性支出模型(ELES)、CD效用函数和门槛回归等方法构建了“纵横双向”识别模型,并实证考察了我国居民消费升级与消费结构状况。研究发现,2010—2020年我... 探究消费升级对于促进共同富裕具有深远意义。基于CFPS 2010—2020年数据,结合扩展线性支出模型(ELES)、CD效用函数和门槛回归等方法构建了“纵横双向”识别模型,并实证考察了我国居民消费升级与消费结构状况。研究发现,2010—2020年我国居民家庭消费结构横向上呈升级趋势,但仍以生存型消费支出为主;细分“三型八类”消费,发现生存型与发展型的消费占比上升,享受型消费存在较大的消费偏好,表现出消费分层特征,且家庭消费结构呈多样化发展趋势;家庭年度总支出的三条约束线分别为60100元、122800元及122900元。纵向上发现预算约束线在不断后移,表明消费结构在不断升级。文章运用多门槛回归方法结合ELES模型构建了消费结构的综合识别模型,以此作为判断消费结构升级与否的依据和标准。 展开更多
关键词 消费升级 elES模型 消费结构 效用函数 门槛回归
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Asymptotic solution for a class of sea-air oscillator model for El Nio-southern oscillation 被引量:39
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作者 莫嘉琪 林万涛 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期370-372,共3页
The El Nifio-Southern Oscillation (ENSO) is an interannual phenomenon involved in the tropical Pacific Oceanatmosphere interactions. In this paper, an asymptotic method of solving the nonlinear equation for the ENSO... The El Nifio-Southern Oscillation (ENSO) is an interannual phenomenon involved in the tropical Pacific Oceanatmosphere interactions. In this paper, an asymptotic method of solving the nonlinear equation for the ENSO model is used. And based on a class of oscillator of ENSO model, the approximate solution of a corresponding problem is studied by employing the perturbation method. Firstly, an ENSO model of nonlinear time delay equation of equatorial Pacific is introduced, Secondly, by using the perturbed method, the zeroth and first order asymptotic perturbed solutions are constructed. Finally, from the comparison of the values for a figure, it is seen that the first asymptotic perturbed solution using the perturbation method has a good accuracy. And it is proved from the results that the perturbation method can be used as an analytic operation for the sea surface temperature anomaly in the equatorial Pacific of the atmosphere-ocean oscillation for the ENSO model. 展开更多
关键词 NONLINEAR perturbation method el Nin^o~Southern Oscillation model
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Asymptotic solution for the El Nio time delay sea-air oscillator model 被引量:6
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作者 莫嘉琪 林万涛 林一骅 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第7期35-40,共6页
A sea-air oscillator model is studied using the time delay theory. The aim is to find an asymptotic solving method for the El Nino-southern oscillation (ENSO) model. Employing the perturbed method, an asymptotic sol... A sea-air oscillator model is studied using the time delay theory. The aim is to find an asymptotic solving method for the El Nino-southern oscillation (ENSO) model. Employing the perturbed method, an asymptotic solution of the corresponding problem is obtained. Thus we can obtain the prognoses of the sea surface temperature (SST) anomaly and the related physical quantities. 展开更多
关键词 nonlinear approximate solution el Nino-Southern oscillator model
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Comparison among the Consumption Structures of Different Income Groups of Urban Residents in Guangxi Based on ELES Model 被引量:2
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作者 HAN Zhi-cheng LI Xiao-xiang LI Zhi-xian 《Asian Agricultural Research》 2011年第1期34-36,76,共4页
According to the household consumption data of urban residents in Guangxi Statistical Yearbook in the year 2009, the ELES (Extended Linear Expenditure System) is used to analyze the consumption structure, the propensi... According to the household consumption data of urban residents in Guangxi Statistical Yearbook in the year 2009, the ELES (Extended Linear Expenditure System) is used to analyze the consumption structure, the propensity to consume, and the consumer flexibility of urban residents in Guangxi Zhuang Autonomous Region of China in the year 2008. Result shows that urban residents in Guangxi has relatively low propensity to consume. And their consumption, especially the middle and low-income families, is mostly concentrated in food, cloth, lodging and other basic necessities of life, which account for more than a half of their income. Based on this, corresponding suggestions are put forward to enlarge the consumption demand of urban residents in Guangxi, such as increasing the regulation of income redistribution, minimizing the gap between the rich and the poor, enhancing the overall consumption level, cultivating the consumption hot spots for the urban residents, and actively guiding the enjoyable consumption. 展开更多
关键词 Consumption structure elES model propensity to consume FLEXIBILITY China
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VARIATIONAL ITERATION SOLVING METHOD FOR SEA-AIR OSCILLATOR MODEL OF INTERDECADAL CLIMATE FLUCTUATIONS 被引量:3
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作者 MO Jia-qi LIN Yi-hua WANG Hui 《Chinese Geographical Science》 SCIE CSCD 2005年第3期227-230,共4页
Atmospheric physics is a very complicated natural phenomenon and needs to simplify its basic models for the sea-air oscillator. And it is solved by using the approximate method. The variational iteration method is a s... Atmospheric physics is a very complicated natural phenomenon and needs to simplify its basic models for the sea-air oscillator. And it is solved by using the approximate method. The variational iteration method is a simple and valid method. In this paper the coupled system for a sea-air oscillator model of interdecadal climate fluctuations is considered. Firstly, through introducing a set of functions, and computing the variations, the Lagrange multipliers are obtained. And then, the generalized expressions of variational iteration are constructed. Finally, through selecting appropriate initial iteration from the iteration expressions, the approximations of solution for the sea-air oscillator model are solved successively. 展开更多
关键词 NONLINEAR variational iteration el Nino-Southern Oscillator model
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Research on Consumption Structure of Rural Residents in Gansu Province Based on ELES Model 被引量:4
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作者 LI Ting-ting,SHI Chang-liang,ZHANG An-liang Beijing Forestry University,Beijing 100045,China 《Asian Agricultural Research》 2011年第9期34-37,共4页
By using cross-section data on consumption structure of rural residents in Gansu Province in 2007 and 2008,this paper adopts ELES model to conduct empirical analysis on consumption structure of rural residents in Gans... By using cross-section data on consumption structure of rural residents in Gansu Province in 2007 and 2008,this paper adopts ELES model to conduct empirical analysis on consumption structure of rural residents in Gansu Province.It indicates that in the current consumption structure of rural residents in Gansu Province,food expenditure is still at the most important and basic level;the overall consumption level of rural residents in Gansu Province is not high;at present,the consumption of rural residents in Gansu Province still hinges in a large measure on income,vulnerable to the price fluctuation.Consequently,increasing farmers' income and stabilizing the level of commodity price,turns out to be a foundation as well as an important approach to improve consumption structure of rural residents in Gansu Province. 展开更多
关键词 elES model CONSUMPTION STRUCTURE RURAL RESIDENTS G
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Asymptotic solving method for a sea air oscillator model of atmospheric physics 被引量:2
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作者 Lin Wan-Tao Lin Yi-Hua Mo Jia-Qi 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期37-40,共4页
In this paper, a class of coupled system for the E1 Nifio/La Nifia southern oscillation (ENSO) atmospheric physics oscillation model is considered. We propose an ENSO atmospheric physics model using a method from th... In this paper, a class of coupled system for the E1 Nifio/La Nifia southern oscillation (ENSO) atmospheric physics oscillation model is considered. We propose an ENSO atmospheric physics model using a method from the asymptotic theory. It is indicated from the results that the asymptotic method can be used for analyzing the sea surface temperature anomaly and the thermocline depth anomaly of the atmosphere-ocean oscillation for the ENSO model in the equatorial Pacific. 展开更多
关键词 nonlinear asymptotic theory el Nifia southern oscillation model
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Convenient Way of Extend Linear Expenditure System Modeling without Regression 被引量:1
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作者 Ningning Song Yiqing Liu 《Open Journal of Statistics》 2015年第6期519-524,共6页
Extend Linear Expenditure System model is a collection of multiple linear models, and modeling is a clearly tedious process. The innovation of this paper is trying to find a simple way of ELES modeling, which means, i... Extend Linear Expenditure System model is a collection of multiple linear models, and modeling is a clearly tedious process. The innovation of this paper is trying to find a simple way of ELES modeling, which means, in order to omit the modeling process one by one, we try to use Excel functionality to create a model workplace. As long as you replace the original sample data in the workspace, you can get the results you want. 展开更多
关键词 elES model OLS WLS
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Perturbation to Noether Symmetries and Adiabatic Invariants for Generalized Birkhoff Systems Based on El-Nabulsi Dynamical Model 被引量:2
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作者 宋传静 张毅 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第4期421-427,共7页
With the action of small perturbation on generalized El-Nabulsi-Birkhoff fractional equations,the perturbation to Noether symmetries and adiabatic invariants are studied under the framework of El-Nabulsi′s fractional... With the action of small perturbation on generalized El-Nabulsi-Birkhoff fractional equations,the perturbation to Noether symmetries and adiabatic invariants are studied under the framework of El-Nabulsi′s fractional model.Firstly,based on the invariance of El-Nabulsi-Pfaff action under the infinitesimal transformations of group,the exact invariants are given.Secondly,on the basis of the definition of higher order adiabatic invariants of a dynamical system,the adiabatic invariants of the Noether symmetric perturbation for disturbed generalized El-Nabulsi′s fractional Birkhoff system are presented under some conditions,and some special cases are discussed.Finally,an example known as Hojman-Urrutia problem is given to illustrate the application of the results. 展开更多
关键词 perturbation to Noether symmetry adiabatic invariant el-Nabulsi dynamical model generalized Birk-hoff system infinitesimal transformation
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Simulating Eastern-and Central-Pacific Type ENSO Using a Simple Coupled Model 被引量:3
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作者 Xianghui FANG Fei ZHENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第6期671-681,共11页
Severe biases exist in state-of-the-art general circulation models(GCMs) in capturing realistic central-Pacific(CP) El Nino structures. At the same time, many observational analyses have emphasized that thermoclin... Severe biases exist in state-of-the-art general circulation models(GCMs) in capturing realistic central-Pacific(CP) El Nino structures. At the same time, many observational analyses have emphasized that thermocline(TH) feedback and zonal advective(ZA) feedback play dominant roles in the development of eastern-Pacific(EP) and CP El Nino-Southern Oscillation(ENSO), respectively. In this work, a simple linear air-sea coupled model, which can accurately depict the strength distribution of the TH and ZA feedbacks in the equatorial Pacific, is used to investigate these two types of El Nino. The results indicate that the model can reproduce the main characteristics of CP ENSO if the TH feedback is switched off and the ZA feedback is retained as the only positive feedback, confirming the dominant role played by ZA feedback in the development of CP ENSO. Further experiments indicate that, through a simple nonlinear control approach, many ENSO characteristics,including the existence of both CP and EP El Nino and the asymmetries between El Nino and La Nina, can be successfully captured using the simple linear air-sea coupled model. These analyses indicate that an accurate depiction of the climatological sea surface temperature distribution and the related ZA feedback, which are the subject of severe biases in GCMs, is very important in simulating a realistic CP El Nino. 展开更多
关键词 central-Pacific el Nino eastern-Pacific el Nino simple coupled model simulation asymmetry
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A unified approach to fuzzy modelling and robust synchronization of different hyperchaotic systems 被引量:4
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作者 张化光 赵琰 +1 位作者 余文 杨东升 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第11期4056-4066,共11页
In this paper, a Takagi Sugeno (T-S) fuzzy model-based method is proposed to deal with the problem of synchronization of two identical or different hyperchaotic systems. The T S fuzzy models with a small number of f... In this paper, a Takagi Sugeno (T-S) fuzzy model-based method is proposed to deal with the problem of synchronization of two identical or different hyperchaotic systems. The T S fuzzy models with a small number of fuzzy IF-THEN rules are employed to represent many typical hyperchaotic systems exactly. The benefit of employing the T-S fuzzy models lies in mathematical simplicity of analysis. Based on the T-S fuzzy hyperchaotic models, two fuzzy controllers arc designed via parallel distributed compensation (PDC) and exact linearization (EL) techniques to synchronize two identical hyperchaotic systems with uncertain parameters and two different hyperchaotic systems, respectively. The sufficient conditions for the robust synchronization of two identical hyperchaotic systems with uncertain parameters and the asymptotic synchronization of two different hyperchaotic systems are derived by applying the Lyapunov stability theory. This method is a universal one of synchronizing two identical or different hyperchaotic systems. Numerical examples are given to demonstrate the validity of the proposed fuzzy model and hyperchaotic synchronization scheme. 展开更多
关键词 hyperchaotic synchronization fuzzy modelling T-S fuzzy model exact linearization el
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Characteristic modemodel of tropical Pacific Ocean and dynamic mechanism of El Nino
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作者 Zhang Xiangdong Huang Shisong and Zhang Jing 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1995年第4期485-498,共14页
In this paper, the tropical Pacific layer model of characteristic modes was developed, which improves andper feets the first vertical baroclinic mode model currently used in ENSO dynamic studies. The dynamic mechanism... In this paper, the tropical Pacific layer model of characteristic modes was developed, which improves andper feets the first vertical baroclinic mode model currently used in ENSO dynamic studies. The dynamic mechanisms andstructures of tropical Pacific thermoclinic depth disturbances were further detected. These studies demonstrate that, inaddition to the momentum exchange between oceanic mixed layer (surface layer) and thermoclinic layer (subsurface layer)which is an important dynamic mechanism triggering the thermoclinic depth disturbances, the vertical sea water mass ex change between oceanic layers plays an important dynamic role in triggering thermoclinic depth disturbances. Both kindsof physical processes excit different kind of dynamic modes and exhibit different structures, respectively. The disturbancesinduced by both kinds of dynamic modes intensify each other. The dynamic mechanism and dynamic processes of El Ninodeveloping are also discussed in the paper. 展开更多
关键词 The Pacific model el Nino
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WIND STRESS ANOMALY MODEL ON ENSO TIME SCALES IN COMPLEX MODELS
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作者 吴秋霞 倪允琪 《Journal of Tropical Meteorology》 SCIE 1998年第1期47-55,共9页
The purpose of this paper is to evaluate the tropical Pacific wind stress anomalies produccd on monthly to interannual time scales by the complex general circulation model (GCM) of the center for Ocean Land Atmosphere... The purpose of this paper is to evaluate the tropical Pacific wind stress anomalies produccd on monthly to interannual time scales by the complex general circulation model (GCM) of the center for Ocean Land Atmosphere Interactions (C.O.L.A.) at low (R15) resolutions. The model is integraed using observed sea surface temperature (SST) for ten years 1979 through 1988. The model simulates generally realistic wind stress anomaly (WSA). The model-generated data set of WSA was used to force the Zebiax Cane ocean model (ZCOM) for ten years. The modeled (SST) anomalies were compared to the observed SST anomalies. The ZCOM simulation shows realistic 1982/83 and 1986/87 warm episodes along the equator, but could produce less realistic 1984/85and 1988/89 cold episodes along the equator due to lack of wind stress forcing in the mean model. Time series of the NINO3 index (measuring the SST anomaly in the mid-eastern Pacific) is realistic for the ZCOM simulation. 展开更多
关键词 ENSO CIRCULATION model simplified model el Nino
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Threshold autoregression models for forecasting El Nino events
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作者 Pu Shuzhen and Yu Huiling First Institute of Oceanography, State Oceanic Administration, Qingdao, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第1期61-67,共7页
-In this paper, monthly mean SST data in a large area are used. After the spacial average of the data is carried out and the secular monthly means are substracted, a time series (Jan. 1951-Dec. 1985) of SST anomalies ... -In this paper, monthly mean SST data in a large area are used. After the spacial average of the data is carried out and the secular monthly means are substracted, a time series (Jan. 1951-Dec. 1985) of SST anomalies of the cold tongue water area in the eastern tropical Pacific Ocean is obtained. On the basis of the time series, an autoregression model, a self-exciting threshold autoregression model and an open loop autoregression model are developed respectively. The interannual variations are simulated by means of those models. The simulation results show that all the three models have made very good hindcasting for the nine El Nino events since 1951. In order to test the reliability of the open loop threshold model, extrapolated forecast was made for the period of Jan. 1986-Feb. 1987. It can be seen from the forecasting that the model could forecast well the beginning and strengthening stages of the recent El Nino event (1986-1987). Correlation coefficients of the estimations to observations are respectively 0. 84, 0. 88 and 0. 89. It is obvious that all the models work well and the open loop threshold one is the best. So the open loop threshold autoregression model is a useful tool for monitoring the SSTinterannual variation of the cold tongue water area in the Eastern Equatorial Pacific Ocean and for estimating the El Nino strength. 展开更多
关键词 Nino EI SSTA Threshold autoregression models for forecasting el Nino events el
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河北省城乡居民消费结构变动研究——基于ELES模型的实证分析 被引量:2
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作者 张静 李志晓 高红志 《沧州师范学院学报》 2024年第1期36-40,共5页
基于ELES模型,对2013-2021年河北省城乡居民消费结构变动情况进行了研究.从边际消费倾向可以看出,随着生活水平的提高,河北省城乡居民的消费逐渐从“温饱型”向“小康型”转变.消费结构变动度分析显示,除个别年份外,居民消费结构整体变... 基于ELES模型,对2013-2021年河北省城乡居民消费结构变动情况进行了研究.从边际消费倾向可以看出,随着生活水平的提高,河北省城乡居民的消费逐渐从“温饱型”向“小康型”转变.消费结构变动度分析显示,除个别年份外,居民消费结构整体变动不大,相对较稳定.通过分析消费结构熵数发现,河北省城乡居民整体消费质量较高,但是消费结构升级速度相对较慢.根据分析结果,提出了增加居民收入、优化消费环境、拓展新型消费、坚持推进城乡融合发展、提高农村居民的社会保障水平等建议. 展开更多
关键词 elES模型 河北省 城乡居民 消费结构
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Groundwater Management at West El-Minia Desert Area, Egypt Using Numerical Modeling
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作者 Ahmed A. Abdel Moneim José Paulino Fernández-Álvarez +1 位作者 Elsayed M. Abu El Ella Ahmed M. Masoud 《Journal of Geoscience and Environment Protection》 2016年第7期66-76,共11页
Water shortage is the main problem facing any development in Egypt especially in the desert lands. River Nile is considered the main source of water in Egypt but its water covers only the area of flood plain where its... Water shortage is the main problem facing any development in Egypt especially in the desert lands. River Nile is considered the main source of water in Egypt but its water covers only the area of flood plain where its tributaries do not reach to the desert. The desert fringes, west of El-Minia governorate, Egypt, are areas of natural expansion for agricultural, industrial, and civil activities. This implies an increasing demand for groundwater. A numerical groundwater model is one of the main tools used for assessment of the resource potential and prediction of future impact under different circumstances and stresses. In this paper, a transient groundwater flow model in the desert district west of El-Minia, Egypt, was developed. The conceptual model was built by analyzing the hydrogeological data and previous work. Steady state model of year 1990 was used to investigate and calibrate the parameters such as hydraulic conductivities, recharge and conductance of the surface water streams. The storage coefficients are calibrated by the transient model based on the available data observed from 1990 to 2013, which provides insights to understand the behavior of groundwater system in Quaternary Aquifer and to predict spatial-temporal distributions of groundwater levels and groundwater flow in responding to extraction of water. The calibrated transient model will be used to predict the impacts of desert development schemes and water resources management schemes on groundwater in the study area. 展开更多
关键词 Groundwater Flow model el-Minia Groundwater Management Quaternary Aquifer
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Climate variability and predictability associated with the Indo-Pacific Oceanic Channel Dynamics in the CCSM4 Coupled System Model 被引量:2
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作者 YUAN Dongliang XU Peng XU Tengfei 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第1期23-38,共16页
An experiment using the Community Climate System Model(CCSM4), a participant of the Coupled Model Intercomparison Project phase-5(CMIP5), is analyzed to assess the skills of this model in simulating and predicting the... An experiment using the Community Climate System Model(CCSM4), a participant of the Coupled Model Intercomparison Project phase-5(CMIP5), is analyzed to assess the skills of this model in simulating and predicting the climate variabilities associated with the oceanic channel dynamics across the Indo-Pacific Oceans. The results of these analyses suggest that the model is able to reproduce the observed lag correlation between the oceanic anomalies in the southeastern tropical Indian Ocean and those in the cold tongue in the eastern equatorial Pacific Ocean at a time lag of 1 year. This success may be largely attributed to the successful simulation of the interannual variations of the Indonesian Throughflow, which carries the anomalies of the Indian Ocean Dipole(IOD) into the western equatorial Pacific Ocean to produce subsurface temperature anomalies, which in turn propagate to the eastern equatorial Pacific to generate ENSO. This connection is termed the "oceanic channel dynamics" and is shown to be consistent with the observational analyses. However, the model simulates a weaker connection between the IOD and the interannual variability of the Indonesian Throughflow transport than found in the observations. In addition, the model overestimates the westerly wind anomalies in the western-central equatorial Pacific in the year following the IOD, which forces unrealistic upwelling Rossby waves in the western equatorial Pacific and downwelling Kelvin waves in the east. This assessment suggests that the CCSM4 coupled climate system has underestimated the oceanic channel dynamics and overestimated the atmospheric bridge processes. 展开更多
关键词 Indian Ocean Dipole el Nino-Southern Oscillations(ENSO) oceanic channel Community Climate System model(CCSM4) Indonesian Throughflow ENSO predictability
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Analysis the Dynamics of SIHR Model: Covid-19 Case in Djibouti 被引量:2
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作者 Yahyeh Souleiman Abdoulrazack Mohamed Liban Ismail 《Applied Mathematics》 2021年第10期867-881,共15页
The Covid-19 epidemic is an emerging infectious disease of the viral zoonosis type caused by the coronavirus strain SARS-CoV-2, it is classified as a human-to-human communicable disease and is currently a pandemic wor... The Covid-19 epidemic is an emerging infectious disease of the viral zoonosis type caused by the coronavirus strain SARS-CoV-2, it is classified as a human-to-human communicable disease and is currently a pandemic worldwide. In this paper, we propose conceptual mathematical models of the epidemic dynamics of four compartments. We have collected data from the Djibouti health ministry. We study the positivity, boundedness, existence and uniqueness of the weak solution. Next, we define the Basic reproduction number by the method of the DFE and EEP. Then, we study the local and global stability and the bifurcation analysis of equilibrium to examine its epidemiological relevance. Finally, we analyze the fit of the data in comparison with the result of our mathematical results, to validate the model and estimate the important model parameters and prediction about the disease. We consider the real cases of Djibouti from 15th March to 15th May 2021. 展开更多
关键词 SIHR model Covid-19 Basic Reproduction Number Stability Analysis Mod-el Validation
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Estimating the Yield Loss of Winter Wheat from Drought in the United States Southern Plains Region as Influenced by El Niño-Southern Oscillation (ENSO)
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作者 Prem Woli Gerald R. Smith +1 位作者 Charles R. Long Francis M. Rouquette, Jr. 《Agricultural Sciences》 2024年第9期1018-1034,共17页
Wheat (Triticum aestivum L.) production is a major economic activity in most regional and rural areas in the Southern Plains, a semi-arid region of the United States. This region is vulnerable to drought and is projec... Wheat (Triticum aestivum L.) production is a major economic activity in most regional and rural areas in the Southern Plains, a semi-arid region of the United States. This region is vulnerable to drought and is projected to experience a drier climate in the future. Since the interannual variability in climate in this region is linked to an ocean-atmospheric phenomenon, called El Niño-Southern Oscillation (ENSO), droughts in this region may be associated with ENSO. Droughts that occur during the critical growth phases of wheat can be extremely costly. However, the losses due to an impending drought can be minimized through mitigation measures if it is predicted in advance. Predicting the yield loss from an imminent drought is crucial for stakeholders. One of the reliable ways for such prediction is using a plant physiology-based agricultural drought index, such as Agricultural Reference Index for Drought (ARID). This study developed ENSO phase-specific, ARID-based models for predicting the drought-induced yield loss for winter wheat in this region by accounting for its phenological phase-specific sensitivity to drought. The reasonable values of the drought sensitivity coefficients of the yield model for each ENSO phase (El Niño, La Niña, or Neutral) indicated that the yield models reflected reasonably well the phenomena of water stress decreasing the winter wheat yields in this region during different ENSO phases. The values of various goodness-of-fit measures used, including the Nash-Sutcliffe Index (0.54 to 0.67), the Willmott Index (0.82 to 0.89), and the percentage error (20 to 26), indicated that the yield models performed fairly well at predicting the ENSO phase-specific loss of wheat yields from drought. This yield model may be useful for predicting yield loss from drought and scheduling irrigation allocation based on the phenological phase-specific sensitivity to drought as impacted by ENSO. 展开更多
关键词 ARID DROUGHT Drought Index ENSO el Niño Growth-Stage model Phenological-Phase Prediction Semi-Arid Wheat Yield Loss
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基于ELES模型的城镇居民生活用水水价支付能力研究——以北京市为例 被引量:28
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作者 陈菁 陈丹 +1 位作者 褚琳琳 陈祥 《水利学报》 EI CSCD 北大核心 2007年第8期1016-1020,共5页
本文从支付能力的角度,根据计量经济学的需求函数理论,以我国城镇居民消费支出结构数据为基础,提出了应用扩展线性支出系统(ELES)模型,分析城镇居民生活用水水价支付能力。以北京市为例,采用1998~2004年截面数据资料,计算分析了不同时... 本文从支付能力的角度,根据计量经济学的需求函数理论,以我国城镇居民消费支出结构数据为基础,提出了应用扩展线性支出系统(ELES)模型,分析城镇居民生活用水水价支付能力。以北京市为例,采用1998~2004年截面数据资料,计算分析了不同时期居民用水需求与水费支出水平、居民用水的边际消费倾向、需求收入弹性以及不同收入户的用水基本需求等,以此定量研究了北京市城镇居民生活用水水价的支付能力。研究结果表明:平均收入水平下,居民对水价具有一定的支付能力,其基本用水需求均能得到满足;可支配收入增长对居民用水需求的影响不大;北京市生活用水水价还有上调的空间,但低收入户的水价支付能力有限,是重点考虑的对象。 展开更多
关键词 城镇居民生活用水 水价 支付能力 elES模型 消费结构 北京市
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