The Advanced Radiative Transfer Modeling System(ARMS),a computationally efficient satellite observation operator,has been successfully integrated into the YinHe four-dimensional variational data assimilation(YH4DVAR)s...The Advanced Radiative Transfer Modeling System(ARMS),a computationally efficient satellite observation operator,has been successfully integrated into the YinHe four-dimensional variational data assimilation(YH4DVAR)system.This study investigates the impacts of assimilating Advanced Microwave Sounding Unit-A(AMSU-A)observations from the Meteorological Operational Satellite-C(MetOp-C)on the performance of YH4DVAR.Through a month-long global statistical analysis and a case study of Typhoon Hinnamnor,we evaluate the benefits of AMSUA data assimilation under clear sky conditions.Key findings are as follows.(1)ARMS achieves simulation accuracy comparable to RTTOV(Radiative Transfer for the Television and InfraRed Observation Satellite Operational Vertical sounder)version 11.2,demonstrating only a 0.5%discrepancy in data retention after quality control.(2)Implementation of ARMS as an operator in YH4DVAR enhances forecast accuracy for the 850-hPa temperature and 500-hPa geopotential height in the tropical region.(3)Compared to RTTOV,ARMS has improved the intensity forecast of Typhoon Hinnamnor and reduced mean wind speed errors by approximately 2%and central pressure errors by approximately1%.ARMS has now been operationally adopted as an alternative observational operator within YH4DVAR,demonstrating exceptional numerical stability,computational efficiency,and promising potential for future satellite data assimilation applications.展开更多
While the scattering phase for several one-dimensional potentials can be exactly derived, less is known in multi-dimensional quantum systems. This work provides a method to extend the one-dimensional phase knowledge t...While the scattering phase for several one-dimensional potentials can be exactly derived, less is known in multi-dimensional quantum systems. This work provides a method to extend the one-dimensional phase knowledge to multi-dimensional quantization rules. The extension is illustrated in the example of Bogomolny's transfer operator method applied in two quantum wells bounded by step potentials of different heights. This generalized semiclassical method accurately determines the energy spectrum of the systems, which indicates the substantial role of the proposed phase correction. Theoretically, the result can be extended to other semiclassical methods, such as Gutzwiller trace formula, dynamical zeta functions, and semielassical Landauer Buttiker formula. In practice, this recipe enhances the applicability of semiclassical methods to multi-dimensional quantum systems bounded by general soft potentials.展开更多
Let T:X → X be an Axiom A diffeomorphism,m the Gibbs state for a Hlder continuous function ɡ. Assume that f:X → R^d is a Hlder continuous function with ∫_X^(fdm) = 0.If the components of f are cohomologously i...Let T:X → X be an Axiom A diffeomorphism,m the Gibbs state for a Hlder continuous function ɡ. Assume that f:X → R^d is a Hlder continuous function with ∫_X^(fdm) = 0.If the components of f are cohomologously independent, then there exists a positive definite symmetric matrix σ~2:=σ~2 (f ) such that S^fn √ n converges in distribution with respect to m to a Gaussian random variable with expectation 0 and covariance matrix σ~2 . Moreover, there exists a real number A 〉 0 such that, for any integer n ≥ 1,Π( m*( 1√ nS f n ),N (0,σ~2 ) ≤A√n, where m*(1√ n S^fn)denotes the distribution of 1√ n S^fn with respect to m, and Π is the Prokhorov metric.展开更多
We prove a generalized Gauss-Kuzmin-L′evy theorem for the generalized Gauss transformation Tp(x) = {p/x}.In addition, we give an estimate for the constant that appears in the theorem.
In this paper, a V-cycle multigrid method is presented for a Hermite rectangular element. By defining proper mesh-dependent inner product and transfer operator, we obtain its convergence property and the uniform conve...In this paper, a V-cycle multigrid method is presented for a Hermite rectangular element. By defining proper mesh-dependent inner product and transfer operator, we obtain its convergence property and the uniform convergence rate independent of mesh size and level are established.展开更多
One of the key elements in real estate management is streamlining the construction process. Thus, the facilities can be built on a faster, cheaper, and higher quality base. Consequently, it will enhance the owner’s c...One of the key elements in real estate management is streamlining the construction process. Thus, the facilities can be built on a faster, cheaper, and higher quality base. Consequently, it will enhance the owner’s competitiveness. Due to the high cost and lengthy duration of mega-construction projects in recent years, Build-Operate-Transfer (BOT) contracts are getting popular in delivering constructed projects in the public sector. With BOT, the public owners are able to focus on the effectiveness of fair resource allocation as well as bring the efficiency of private enterprise into governmental operations. This paper uses Taiwan High Speed Rail project to exemplify the BOT method in executing the constructed projects in the chain of real estate management processes. The paper explains the reasons for building HSR and adopting BOT approach. The detail of the HSR project and the feasibility analysis of the project will be presented in this paper. The feasibility analysis comprises the comparisons of different transportation means, the financial analysis, and other benefits from HSR. Finally, conclusions will be drawn.展开更多
We consider Young's nonuniformly hyperbolic system (X, T, u) where u is the SRB measure corresponding to the system (X, T), and show that if the components of a Holder observable f : X → R^d are cohomologously ...We consider Young's nonuniformly hyperbolic system (X, T, u) where u is the SRB measure corresponding to the system (X, T), and show that if the components of a Holder observable f : X → R^d are cohomologously independent, then f satisfies the multidimensional central limit theorem. Moreover if f is aperiodic, then f satisfies the local multidimensional central limit theorem.展开更多
基金Supported by the National Key Research and Development Program of China(2021YFC3101500)National Natural Science Foundation of China(42075149,42375155,and 62372460)Natural Science Foundation of Hunan Province of China(2023JJ40667)。
文摘The Advanced Radiative Transfer Modeling System(ARMS),a computationally efficient satellite observation operator,has been successfully integrated into the YinHe four-dimensional variational data assimilation(YH4DVAR)system.This study investigates the impacts of assimilating Advanced Microwave Sounding Unit-A(AMSU-A)observations from the Meteorological Operational Satellite-C(MetOp-C)on the performance of YH4DVAR.Through a month-long global statistical analysis and a case study of Typhoon Hinnamnor,we evaluate the benefits of AMSUA data assimilation under clear sky conditions.Key findings are as follows.(1)ARMS achieves simulation accuracy comparable to RTTOV(Radiative Transfer for the Television and InfraRed Observation Satellite Operational Vertical sounder)version 11.2,demonstrating only a 0.5%discrepancy in data retention after quality control.(2)Implementation of ARMS as an operator in YH4DVAR enhances forecast accuracy for the 850-hPa temperature and 500-hPa geopotential height in the tropical region.(3)Compared to RTTOV,ARMS has improved the intensity forecast of Typhoon Hinnamnor and reduced mean wind speed errors by approximately 2%and central pressure errors by approximately1%.ARMS has now been operationally adopted as an alternative observational operator within YH4DVAR,demonstrating exceptional numerical stability,computational efficiency,and promising potential for future satellite data assimilation applications.
基金Supported by the National Science Council at Taiwan through Grants No. NSC 97-2112-M-009-008-MY3
文摘While the scattering phase for several one-dimensional potentials can be exactly derived, less is known in multi-dimensional quantum systems. This work provides a method to extend the one-dimensional phase knowledge to multi-dimensional quantization rules. The extension is illustrated in the example of Bogomolny's transfer operator method applied in two quantum wells bounded by step potentials of different heights. This generalized semiclassical method accurately determines the energy spectrum of the systems, which indicates the substantial role of the proposed phase correction. Theoretically, the result can be extended to other semiclassical methods, such as Gutzwiller trace formula, dynamical zeta functions, and semielassical Landauer Buttiker formula. In practice, this recipe enhances the applicability of semiclassical methods to multi-dimensional quantum systems bounded by general soft potentials.
基金supported by the National Natural Science Foundation of China(10571174)the Scientific Research Foundation of Ministry of Education for Returned Overseas Chinese ScholarsScientific Research Foundation of Ministry of Human Resources and Social Security for Returned Overseas Chinese Scholars
文摘Let T:X → X be an Axiom A diffeomorphism,m the Gibbs state for a Hlder continuous function ɡ. Assume that f:X → R^d is a Hlder continuous function with ∫_X^(fdm) = 0.If the components of f are cohomologously independent, then there exists a positive definite symmetric matrix σ~2:=σ~2 (f ) such that S^fn √ n converges in distribution with respect to m to a Gaussian random variable with expectation 0 and covariance matrix σ~2 . Moreover, there exists a real number A 〉 0 such that, for any integer n ≥ 1,Π( m*( 1√ nS f n ),N (0,σ~2 ) ≤A√n, where m*(1√ n S^fn)denotes the distribution of 1√ n S^fn with respect to m, and Π is the Prokhorov metric.
文摘We prove a generalized Gauss-Kuzmin-L′evy theorem for the generalized Gauss transformation Tp(x) = {p/x}.In addition, we give an estimate for the constant that appears in the theorem.
基金Supported by NSF of China(10971203)Supported by the NSF of the education Department of Henan Province (2009A110017)
文摘In this paper, a V-cycle multigrid method is presented for a Hermite rectangular element. By defining proper mesh-dependent inner product and transfer operator, we obtain its convergence property and the uniform convergence rate independent of mesh size and level are established.
文摘One of the key elements in real estate management is streamlining the construction process. Thus, the facilities can be built on a faster, cheaper, and higher quality base. Consequently, it will enhance the owner’s competitiveness. Due to the high cost and lengthy duration of mega-construction projects in recent years, Build-Operate-Transfer (BOT) contracts are getting popular in delivering constructed projects in the public sector. With BOT, the public owners are able to focus on the effectiveness of fair resource allocation as well as bring the efficiency of private enterprise into governmental operations. This paper uses Taiwan High Speed Rail project to exemplify the BOT method in executing the constructed projects in the chain of real estate management processes. The paper explains the reasons for building HSR and adopting BOT approach. The detail of the HSR project and the feasibility analysis of the project will be presented in this paper. The feasibility analysis comprises the comparisons of different transportation means, the financial analysis, and other benefits from HSR. Finally, conclusions will be drawn.
文摘We consider Young's nonuniformly hyperbolic system (X, T, u) where u is the SRB measure corresponding to the system (X, T), and show that if the components of a Holder observable f : X → R^d are cohomologously independent, then f satisfies the multidimensional central limit theorem. Moreover if f is aperiodic, then f satisfies the local multidimensional central limit theorem.