東華大學圖書館 |

語系: 繁體中文

說明(常見問題)

回圖書館首頁

手機版館藏查詢

登入

回首頁

切換: 標籤 | MARC模式 | ISBD

Deterministic and stochastic aspects...

Akella, Santharam.

FindBook

Google Book

Amazon

博客來

Deterministic and stochastic aspects of data assimilation.

紀錄類型:	書目-語言資料,印刷品 : Monograph/item
正題名/作者:	Deterministic and stochastic aspects of data assimilation./
作者:	Akella, Santharam.
面頁冊數:	124 p.
附註:	Adviser: Ionel Michael Navon.
Contained By:	Dissertation Abstracts International67-04B.
標題:	Geophysics. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3216462
ISBN:	9780542659591

Deterministic and stochastic aspects of data assimilation.
Akella, Santharam.

Deterministic and stochastic aspects of data assimilation. - 124 p.

Adviser: Ionel Michael Navon.

Thesis (Ph.D.)--The Florida State University, 2006.

The principles of optimal control of distributed parameter systems are used to derive a powerful class of numerical methods for solutions of inverse problems, called data assimilation (DA) methods. Using these DA methods one can efficiently estimate the state of a system and its evolution. This information is very crucial for achieving more accurate long term forecasts of complex systems, for instance, the atmosphere. DA methods achieve their goal of optimal estimation via combination of all available information in the form of measurements of the state of the system and a dynamical model which describes the evolution of the system. In this dissertation work, we study the impact of new nonlinear numerical models on DA.

ISBN: 9780542659591Subjects--Topical Terms:

535228
Geophysics.

Deterministic and stochastic aspects of data assimilation.
LDR:03390nam 2200313 a 45 001 967355
005 20110915
008 110915s2006 eng d
020 $a 9780542659591
035 $a (UMI)AAI3216462
035 $a AAI3216462
040 $a UMI $c UMI
100 1 $a Akella, Santharam. $3 1291233
245 1 0 $a Deterministic and stochastic aspects of data assimilation.
300 $a 124 p.
500 $a Adviser: Ionel Michael Navon.
500 $a Source: Dissertation Abstracts International, Volume: 67-04, Section: B, page: 2025.
502 $a Thesis (Ph.D.)--The Florida State University, 2006.
520 $a The principles of optimal control of distributed parameter systems are used to derive a powerful class of numerical methods for solutions of inverse problems, called data assimilation (DA) methods. Using these DA methods one can efficiently estimate the state of a system and its evolution. This information is very crucial for achieving more accurate long term forecasts of complex systems, for instance, the atmosphere. DA methods achieve their goal of optimal estimation via combination of all available information in the form of measurements of the state of the system and a dynamical model which describes the evolution of the system. In this dissertation work, we study the impact of new nonlinear numerical models on DA.
520 $a High resolution advection schemes have been developed and studied to model propagation of flows involving sharp fronts and shocks. The impact of high resolution advection schemes in the framework of inverse problem solution/DA has been studied only in the context of linear models. A detailed study of the impact of various slope limiters and the piecewise parabolic method (PPM) on DA is the subject of this work. In 1-D we use a nonlinear viscous Burgers equation and in 2-D a global nonlinear shallow water model has been used.
520 $a The results obtained show that using the various advection schemes consistently improves variational data assimilation (VDA) in the strong constraint form, which does not include model error. However, the cost functional included efficient, and physically meaningful construction of the background cost functional term, Tb using balance and diffusion equation based correlation operators. This was then followed by an in-depth study of various approaches to model the systematic component of model error in the framework of a weak constraint VDA. Three simple forms, decreasing, invariant, and exponentially increasing in time forms of evolution of model error were tested. The inclusion of model error provides a substantial reduction in forecasting errors, in particular the exponentially increasing form in conjunction with the piecewise parabolic high resolution advection scheme was found to provide the best results.
520 $a Results obtained in this work can be used to formulate sophisticated forms of model errors, and could lead to implementation of new VDA methods using numerical weather prediction models which involve high resolution advection schemes such as the van Leer slope limiters and the PPM.
590 $a School code: 0071.
650 4 $a Geophysics. $3 535228
650 4 $a Mathematics. $3 515831
690 $a 0373
690 $a 0405
710 2 0 $a The Florida State University. $3 1017727
773 0 $t Dissertation Abstracts International $g 67-04B.
790 $a 0071
790 1 0 $a Navon, Ionel Michael, $e advisor
791 $a Ph.D.
792 $a 2006
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3216462