In order to enhance the accuracy and reliability of wireless location under non-line-of-sight (NLOS) environments,a novel neural network (NN) location approach using the digital broadcasting signals is presented. ...In order to enhance the accuracy and reliability of wireless location under non-line-of-sight (NLOS) environments,a novel neural network (NN) location approach using the digital broadcasting signals is presented. By the learning ability of the NN and the closely approximate unknown function to any degree of desired accuracy,the input-output mapping relationship between coordinates and the measurement data of time of arrival (TOA) and time difference of arrival (TDOA) is established. A real-time learning algorithm based on the extended Kalman filter (EKF) is used to train the multilayer perceptron (MLP) network by treating the linkweights of a network as the states of the nonlinear dynamic system. Since the EKF-based learning algorithm approximately gives the minimum variance estimate of the linkweights,the convergence is improved in comparison with the backwards error propagation (BP) algorithm. Numerical results illustrate thatthe proposedalgorithmcanachieve enhanced accuracy,and the performance ofthe algorithmis betterthanthat of the BP-based NN algorithm and the least squares (LS) algorithm in the NLOS environments. Moreover,this location method does not depend on a particular distribution of the NLOS error and does not need line-of-sight ( LOS ) or NLOS identification.展开更多
Urban-related warming in two first-tier cities(Guangzhou and Shenzhen)in southern China with similar large-scale climatic backgrounds was compared using the nested weather research and forecasting regional climate mod...Urban-related warming in two first-tier cities(Guangzhou and Shenzhen)in southern China with similar large-scale climatic backgrounds was compared using the nested weather research and forecasting regional climate model.The default urban data in the model were replaced by reconstructed annual urban data retrieved from satellite-based images for both coarse-(including all of China)and fine-resolution domains(eastern China and three city clusters in China:Beijing– Tianjin–Hebei(BTH),the Yangtze River Delta(YRD),and the Pearl River Delta(PRD)),which reproduced urban surface expansion during the past few decades.The results showed that the 37-year(1980–2016)area-averaged annual urban-related warming was similar(0.69°C/0.64°C)between the urban areas of Guangzhou/Shenzhen;however,the values across the entire area of the two cities varied(0.21°C/0.45°C).Seasonal characteristics could be detected for mean surface air temperatures(SAT)at 2 m,SAT maximum and minimum,and diurnal temperature range(DTR).Both the SAT maximum and minimum generally increased,especially over urban areas;however,changes in the SAT minimum were larger,which induced a decrease in DTR.The DTR in summer decreased by-0.25°C/-0.86°C across the entire area of the two cities and decreased by-0.93°C/-1.15°C over urban areas.The contributions of urban surface expansion to regional warming across the entire area of the two cities were approximately 17%/35%of the overall warming and much greater over Shenzhen.However,the values over urban areas were much closer to the values from total warming(35%/44%).展开更多
In this paper, based on a new more general ansitz, a new algebraic method, named generalized Riccati equation rational expansion method, is devised for constructing travelling wave solutions for nonlinear evolution eq...In this paper, based on a new more general ansitz, a new algebraic method, named generalized Riccati equation rational expansion method, is devised for constructing travelling wave solutions for nonlinear evolution equations with nonlinear terms of any order. Compared with most existing tanh methods for finding travelling wave solutions, the proposed method not only recovers the results by most known algebraic methods, but also provides new and more general solutions. We choose the generalized Burgers-Fisher equation with nonlinear terms of any order to illustrate our method. As a result, we obtain several new kinds of exact solutions for the equation. This approach can also be applied to other nonlinear evolution equations with nonlinear terms of any order.展开更多
We introduce generalized excellent extension of ring R in [4]. If S is a generalized excellent extension of R, we prove that (1) wgldim S≤ wgldim R and glodim S≤ gldim R; (2) the relations between rings R and rings S.
Suppose f is an almost starlike function of order α on the unit disk D. In this paper, we will prove that Фn,β2,γ2,…βn,γn(f)(z)=(f(z1),(f(z1)/z1)^β2(f'(z1))^γ2 z2,…,(f(z1)/z1)^βn(f'(z...Suppose f is an almost starlike function of order α on the unit disk D. In this paper, we will prove that Фn,β2,γ2,…βn,γn(f)(z)=(f(z1),(f(z1)/z1)^β2(f'(z1))^γ2 z2,…,(f(z1)/z1)^βn(f'(z1))^γnzn)1 preserves almost starlikeness of order α on Ωn,p2,…,pn={z=(z1,z2,…,zn)'∈Cn:∑^n j=1|zj|^pj〈1},where 0〈p1≤2,pj≥1,j=2,…,n,are real numbers.展开更多
Directed diffusion is a data dissemination protocol for wireless sensor networks. In directed diffusion, flooding is used for dissemination of interest and exploratory data, which will bring broadcast storm resulting ...Directed diffusion is a data dissemination protocol for wireless sensor networks. In directed diffusion, flooding is used for dissemination of interest and exploratory data, which will bring broadcast storm resulting in substantial energy consumption of networks. A grid-based directed diffusion is presented to improve the energy efficiency of directed diffusion. Virtual geographic grid clusters are constructed by self-organization of nodes using geographic location information. The flooding of interest and exploratory data of original directed diffusion is limited in cluster head nodes. The simulation results and testbed experiments show that the method effectively reduces the network energy consumption. This gain is not achieved at the cost of either delivery ratio or the delay. Importantly, the decreased load also leads to a better delivery ratio and lower delay.展开更多
This paper is devoted to the study of functional variable separation for extended nonlinear elliptic equations. By applying the functional variable separation approach to extended nonlinear elliptic equations via the ...This paper is devoted to the study of functional variable separation for extended nonlinear elliptic equations. By applying the functional variable separation approach to extended nonlinear elliptic equations via the generalized conditional symmetry, we obtain complete classification of those equations which admit functional separable solutions (FSSs) and construct some exact FSSs to the resulting equations.展开更多
In this paper, we introduce the generalized R oper-Suffridge extension operator for locally biholomorphic mappings. It is sh own that this operator preserves the starlikeness on some Reinhardt domains and does not pre...In this paper, we introduce the generalized R oper-Suffridge extension operator for locally biholomorphic mappings. It is sh own that this operator preserves the starlikeness on some Reinhardt domains and does not preserve convexity for some cases. Meanwhile, the growth theorem and di stortion theorem of the corresponding mappings are given.展开更多
This paper presents the popularization of the weighting of Chebyshev's inequality and discusses the relation between this popularization and some famous inequalities.
The generalized conditional symmetry approach is applied to study the variable separation of the extended wave equations. Complete classification of those equations admitting functional separable solutions is obtained...The generalized conditional symmetry approach is applied to study the variable separation of the extended wave equations. Complete classification of those equations admitting functional separable solutions is obtained and exact separable solutions to some of the resulting equations are constructed.展开更多
The Beurling-Ahlfors’ extension is studied under relatively general conditions and its dilatation fonction is estimated. Particularly, the classic Deurling -Ahlfors’ theorem can be obtained under the M-condition.
The solution of nonlinear parabolic equation arising from population dynamics with boundary and initial value are established by the finite difference method,as well as it denotes the unique generalized global solution.
We have considered the basic dynamic homogeneous system of partial differential equations of generalized Green-Lindsay couple-stress thermodiffusion on the plane for homogeneous, isotropic elastic media with the centr...We have considered the basic dynamic homogeneous system of partial differential equations of generalized Green-Lindsay couple-stress thermodiffusion on the plane for homogeneous, isotropic elastic media with the centre of symmetry. We have constructed regular solution of the boundary problems on the line. In the works are obtained in quadrates the solution of the boundary-value problem of the generalized Green-Lindsay theory of couple-stress thermodiffusion, when on border of area are given: the component of normal of displacement vector, the component of touching of stress vector, rotations, flow of heat and flow of diffusion.展开更多
Based on the panel data of Guangxi from 2005 to 2017,the spatiotemporal characteristics and determinants of urban carbon emissions in Guangxi were analyzed using the extended STIRPAT model and the Geographically and T...Based on the panel data of Guangxi from 2005 to 2017,the spatiotemporal characteristics and determinants of urban carbon emissions in Guangxi were analyzed using the extended STIRPAT model and the Geographically and Temporally Weighted Regression(GTWR)model.The main findings of our research can be summarized as follows.While the total carbon emissions of cities in Guangxi consistently increased from 2005 to 2014,the growth trend slowed after 2014,leading to a stabilization in the total emissions.In addition,there are significant differences in the total carbon emissions among the cities.The central and northeastern regions have higher emissions,while the southwestern region has lower emissions.Finally,there are variations in the degrees and directions of the impacts that factors have on carbon emissions among the different time periods and cities.Urban land use is a key factor driving carbon emissions,and it has a negative impact on most cities in Guangxi.Meanwhile,factors such as industrial structure,population urbanization,population concentration,and economic growth have significant positive effects on carbon emissions in Guangxi.The influence of urban roads on carbon emissions is generally positive,while the degree of openness to the outside world and environmental regulations has relatively weaker impacts on emissions.In summary,in order to promote the low-carbon transition of Guangxi and achieve high-quality development,the cities in Guangxi should implement differentiated urban carbon reduction strategies that are focused on optimizing urban land use and industrial structure.展开更多
基金The National High Technology Research and Development Program of China (863 Program) (No.2008AA01Z227)the Cultivatable Fund of the Key Scientific and Technical Innovation Project of Ministry of Education of China (No.706028)
文摘In order to enhance the accuracy and reliability of wireless location under non-line-of-sight (NLOS) environments,a novel neural network (NN) location approach using the digital broadcasting signals is presented. By the learning ability of the NN and the closely approximate unknown function to any degree of desired accuracy,the input-output mapping relationship between coordinates and the measurement data of time of arrival (TOA) and time difference of arrival (TDOA) is established. A real-time learning algorithm based on the extended Kalman filter (EKF) is used to train the multilayer perceptron (MLP) network by treating the linkweights of a network as the states of the nonlinear dynamic system. Since the EKF-based learning algorithm approximately gives the minimum variance estimate of the linkweights,the convergence is improved in comparison with the backwards error propagation (BP) algorithm. Numerical results illustrate thatthe proposedalgorithmcanachieve enhanced accuracy,and the performance ofthe algorithmis betterthanthat of the BP-based NN algorithm and the least squares (LS) algorithm in the NLOS environments. Moreover,this location method does not depend on a particular distribution of the NLOS error and does not need line-of-sight ( LOS ) or NLOS identification.
基金supported by the National Natural Science Foundation of China(Grant Nos.41775087 and 41675149)the National Key Research and Development Program of China(Grant No.2016YFA0600403)+1 种基金the Chinese Academy of Sciences Strategic Priority Program(Grant No.XDA05090206)the Jiangsu Collaborative Innovation Center for Climatic Change
文摘Urban-related warming in two first-tier cities(Guangzhou and Shenzhen)in southern China with similar large-scale climatic backgrounds was compared using the nested weather research and forecasting regional climate model.The default urban data in the model were replaced by reconstructed annual urban data retrieved from satellite-based images for both coarse-(including all of China)and fine-resolution domains(eastern China and three city clusters in China:Beijing– Tianjin–Hebei(BTH),the Yangtze River Delta(YRD),and the Pearl River Delta(PRD)),which reproduced urban surface expansion during the past few decades.The results showed that the 37-year(1980–2016)area-averaged annual urban-related warming was similar(0.69°C/0.64°C)between the urban areas of Guangzhou/Shenzhen;however,the values across the entire area of the two cities varied(0.21°C/0.45°C).Seasonal characteristics could be detected for mean surface air temperatures(SAT)at 2 m,SAT maximum and minimum,and diurnal temperature range(DTR).Both the SAT maximum and minimum generally increased,especially over urban areas;however,changes in the SAT minimum were larger,which induced a decrease in DTR.The DTR in summer decreased by-0.25°C/-0.86°C across the entire area of the two cities and decreased by-0.93°C/-1.15°C over urban areas.The contributions of urban surface expansion to regional warming across the entire area of the two cities were approximately 17%/35%of the overall warming and much greater over Shenzhen.However,the values over urban areas were much closer to the values from total warming(35%/44%).
基金The project partially supported by the State Key Basic Research Program of China under Grant No. 2004CB318000
文摘In this paper, based on a new more general ansitz, a new algebraic method, named generalized Riccati equation rational expansion method, is devised for constructing travelling wave solutions for nonlinear evolution equations with nonlinear terms of any order. Compared with most existing tanh methods for finding travelling wave solutions, the proposed method not only recovers the results by most known algebraic methods, but also provides new and more general solutions. We choose the generalized Burgers-Fisher equation with nonlinear terms of any order to illustrate our method. As a result, we obtain several new kinds of exact solutions for the equation. This approach can also be applied to other nonlinear evolution equations with nonlinear terms of any order.
文摘We introduce generalized excellent extension of ring R in [4]. If S is a generalized excellent extension of R, we prove that (1) wgldim S≤ wgldim R and glodim S≤ gldim R; (2) the relations between rings R and rings S.
基金Supported by the National Natural Science Foundation of China(10626015,10571044)Supported by the Guangdong Natural Science Foundation(06301315)+1 种基金Supported by the Doctoral Foundation of Zhanjiang Normal University(Z0420)Supported by the Natural Science Foundation of Henan University(XK03YBSX200)
文摘Suppose f is an almost starlike function of order α on the unit disk D. In this paper, we will prove that Фn,β2,γ2,…βn,γn(f)(z)=(f(z1),(f(z1)/z1)^β2(f'(z1))^γ2 z2,…,(f(z1)/z1)^βn(f'(z1))^γnzn)1 preserves almost starlikeness of order α on Ωn,p2,…,pn={z=(z1,z2,…,zn)'∈Cn:∑^n j=1|zj|^pj〈1},where 0〈p1≤2,pj≥1,j=2,…,n,are real numbers.
基金the National High Technology Research and Development Programme of China(No.2002AA142020)the National Natural Science Foundation of China(No.60475012)
文摘Directed diffusion is a data dissemination protocol for wireless sensor networks. In directed diffusion, flooding is used for dissemination of interest and exploratory data, which will bring broadcast storm resulting in substantial energy consumption of networks. A grid-based directed diffusion is presented to improve the energy efficiency of directed diffusion. Virtual geographic grid clusters are constructed by self-organization of nodes using geographic location information. The flooding of interest and exploratory data of original directed diffusion is limited in cluster head nodes. The simulation results and testbed experiments show that the method effectively reduces the network energy consumption. This gain is not achieved at the cost of either delivery ratio or the delay. Importantly, the decreased load also leads to a better delivery ratio and lower delay.
基金The project supported by National Natural Science Foundation of China under Grant No. 10447007 and the Natural Science Foundation of Shaanxi Province of China under Grant No. 2005A13
文摘This paper is devoted to the study of functional variable separation for extended nonlinear elliptic equations. By applying the functional variable separation approach to extended nonlinear elliptic equations via the generalized conditional symmetry, we obtain complete classification of those equations which admit functional separable solutions (FSSs) and construct some exact FSSs to the resulting equations.
文摘In this paper, we introduce the generalized R oper-Suffridge extension operator for locally biholomorphic mappings. It is sh own that this operator preserves the starlikeness on some Reinhardt domains and does not preserve convexity for some cases. Meanwhile, the growth theorem and di stortion theorem of the corresponding mappings are given.
文摘This paper presents the popularization of the weighting of Chebyshev's inequality and discusses the relation between this popularization and some famous inequalities.
文摘The generalized conditional symmetry approach is applied to study the variable separation of the extended wave equations. Complete classification of those equations admitting functional separable solutions is obtained and exact separable solutions to some of the resulting equations are constructed.
文摘The Beurling-Ahlfors’ extension is studied under relatively general conditions and its dilatation fonction is estimated. Particularly, the classic Deurling -Ahlfors’ theorem can be obtained under the M-condition.
文摘The solution of nonlinear parabolic equation arising from population dynamics with boundary and initial value are established by the finite difference method,as well as it denotes the unique generalized global solution.
文摘We have considered the basic dynamic homogeneous system of partial differential equations of generalized Green-Lindsay couple-stress thermodiffusion on the plane for homogeneous, isotropic elastic media with the centre of symmetry. We have constructed regular solution of the boundary problems on the line. In the works are obtained in quadrates the solution of the boundary-value problem of the generalized Green-Lindsay theory of couple-stress thermodiffusion, when on border of area are given: the component of normal of displacement vector, the component of touching of stress vector, rotations, flow of heat and flow of diffusion.
基金The Guangxi Key Research and Development Program(AB22035060)The National Natural Science Foundation of China(32060369)+1 种基金TheGuangxi Academy of Sciences Basic Scientific Research Operation Fund Project(2019YJJ1009CQZ-D-1904).
文摘Based on the panel data of Guangxi from 2005 to 2017,the spatiotemporal characteristics and determinants of urban carbon emissions in Guangxi were analyzed using the extended STIRPAT model and the Geographically and Temporally Weighted Regression(GTWR)model.The main findings of our research can be summarized as follows.While the total carbon emissions of cities in Guangxi consistently increased from 2005 to 2014,the growth trend slowed after 2014,leading to a stabilization in the total emissions.In addition,there are significant differences in the total carbon emissions among the cities.The central and northeastern regions have higher emissions,while the southwestern region has lower emissions.Finally,there are variations in the degrees and directions of the impacts that factors have on carbon emissions among the different time periods and cities.Urban land use is a key factor driving carbon emissions,and it has a negative impact on most cities in Guangxi.Meanwhile,factors such as industrial structure,population urbanization,population concentration,and economic growth have significant positive effects on carbon emissions in Guangxi.The influence of urban roads on carbon emissions is generally positive,while the degree of openness to the outside world and environmental regulations has relatively weaker impacts on emissions.In summary,in order to promote the low-carbon transition of Guangxi and achieve high-quality development,the cities in Guangxi should implement differentiated urban carbon reduction strategies that are focused on optimizing urban land use and industrial structure.