Advanced search options

Sorted by: relevance · author · university · date | New search

You searched for `subject:(Kuhn Tucker Systems)`

.
Showing records 1 – 3 of
3 total matches.

▼ Search Limiters

University of South Florida

1. Sivaraman, Vijayaraghavan. A Theoretical and Methodological Framework to Analyze Long Distance Pleasure Travel.

Degree: 2015, University of South Florida

URL: https://scholarcommons.usf.edu/etd/6026

The United States (US) witnessed remarkable growth in annual long distance travel over the past few decades. Over half of the long distance travel in the US is made for pleasure, including visiting friends and relatives (VFR) and leisure activities. This trend could continue with increased use of information and communication technologies for socialization, and enhanced mobility being achieved using fuel-efficient (electric/hybrid) and technology enhanced vehicles. Despite these developments, and recent interest to implement alternate mass transit options to serve this market, not much exists on the measurement, analysis and modeling of long distance pleasure travel in the U.S.
Statewide and national models are used to estimate long distance travel, but these are predominantly trip-based models, making it difficult to understand long distance trips as collection of household-level travel behavior. This form of travel behavior has been studied a lot in tourism, but in a piecemeal manner, such as to (from) a specific destination. Further, most of these studies are confined to analyzing leisure market, with VFR market gaining recognition only recently. In essence, annual household long distance pleasure travel behavior needs to be studied in a comprehensive manner rather than as isolated trips. This is because, most of these household travel decisions are undertaken considering their annual time and monetary budget, and their perceived cost to travel to one (or more) destination for given pleasure purpose on one (or more) occasion using a given mode of travel. Thus, the main objective of this dissertation is to develop a comprehensive behavioral model framework to analyze the above-discussed annual household long distance pleasure travel choices.
To start the above effort, it is first required to collect detailed annual household travel data, last collected over two decades ago (e.g.: ATS, 1995). No such recent effort has been pursued due to the significant labor and economic resource required to undertake it. There exist recent surveys (NHTS, 2001), but collected over a shorter (four week) period, and require significant processing even to arrive at aggregate annual travel estimates. Second, besides surveys, there is a need for additional data to estimate households’ annual pleasure travel budget, and their cost to travel and stay at each of their potential destination choices, which are not readily available.
Thus, as the first goal, this dissertation analyzes long distance travel reported across historical surveys (NPTS; ATS; NHTS), to understand the differences in their definition, enumeration of purpose and collection methods. The intent here is twofold, first to conceive a method to estimate annual travel from surveys with shorter collection period. Further, the second intent is to gather travel patterns from these historical datasets such that it informs the second goal of this dissertation, i.e. development of a behavioral framework to analyze annual household pleasure travel. To this effect, this research also…

Subjects/Keywords: MDCEV; VFR; Multiple Constraint Choice Models; Kuhn Tucker Systems; Economics; Mathematics; Urban Studies and Planning

Record Details Similar Records

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^{th} Edition):

Sivaraman, V. (2015). A Theoretical and Methodological Framework to Analyze Long Distance Pleasure Travel. (Thesis). University of South Florida. Retrieved from https://scholarcommons.usf.edu/etd/6026

Note: this citation may be lacking information needed for this citation format:

Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^{th} Edition):

Sivaraman, Vijayaraghavan. “A Theoretical and Methodological Framework to Analyze Long Distance Pleasure Travel.” 2015. Thesis, University of South Florida. Accessed November 28, 2020. https://scholarcommons.usf.edu/etd/6026.

Note: this citation may be lacking information needed for this citation format:

Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^{th} Edition):

Sivaraman, Vijayaraghavan. “A Theoretical and Methodological Framework to Analyze Long Distance Pleasure Travel.” 2015. Web. 28 Nov 2020.

Vancouver:

Sivaraman V. A Theoretical and Methodological Framework to Analyze Long Distance Pleasure Travel. [Internet] [Thesis]. University of South Florida; 2015. [cited 2020 Nov 28]. Available from: https://scholarcommons.usf.edu/etd/6026.

Note: this citation may be lacking information needed for this citation format:

Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Sivaraman V. A Theoretical and Methodological Framework to Analyze Long Distance Pleasure Travel. [Thesis]. University of South Florida; 2015. Available from: https://scholarcommons.usf.edu/etd/6026

Not specified: Masters Thesis or Doctoral Dissertation

Virginia Tech

2.
Battermann, Astrid.
Preconditioning of Karush – Kuhn – *Tucker* *Systems* arising in Optimal Control Problems.

Degree: MS, Mathematics, 1996, Virginia Tech

URL: http://hdl.handle.net/10919/9579

This work is concerned with the construction of preconditioners for indefinite linear systems. The systems under investigation arise in the numerical solution of quadratic programming problems, for example in the form of Karush – Kuhn – Tucker (KKT) optimality conditions or in interior – point methods. Therefore, the system matrix is referred to as a KKT matrix. It is not the purpose of this thesis to investigate systems arising from general quadratic programming problems, but to study systems arising in linear quadratic control problems governed by partial differential equations.
The KKT matrix is symmetric, nonsingular, and indefinite. For the solution of the linear systems generalizations of the conjugate gradient method, MINRES and SYMMLQ, are used. The performance of these iterative solution methods depends on the eigenvalue distribution of the matrix and of the cost of the multiplication of the system matrix with a vector. To increase the performance of these methods, one tries to transform the system to favorably change its eigenvalue distribution. This is called preconditioning and the nonsingular transformation matrices are called preconditioners. Since the overall performance of the iterative methods also depends on the cost of matrix – vector multiplications, the preconditioner has to be constructed so that it can be applied efficiently.
The preconditioners designed in this thesis are positive definite and they maintain the symmetry of the system. For the construction of the preconditioners we strongly exploit the structure of the underlying system. The preconditioners are composed of preconditioners for the submatrices in the KKT system. Therefore, known efficient preconditioners can be readily adapted to this context. The derivation of the preconditioners is motivated by the properties of the KKT matrices arising in optimal control problems. An analysis of the preconditioners is given and various cases which are important for interior point methods are treated separately. The preconditioners are tested on a typical problem, a Neumann boundary control for an elliptic equation. In many important situations the preconditioners substantially reduce the number of iterations needed by the solvers. In some cases, it can even be shown that the number of iterations for the preconditioned system is independent of the refinement of the discretization of the partial differential equation.
*Advisors/Committee Members: Heinkenschloss, Matthias (committeechair), Burns, John A. (committee member), Beattie, Christopher A. (committee member).*

Subjects/Keywords: preconditioning; optimal control; quadratic programming; karush-kuhn-tucker systems; indefinite systems

Record Details Similar Records

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^{th} Edition):

Battermann, A. (1996). Preconditioning of Karush – Kuhn – Tucker Systems arising in Optimal Control Problems. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/9579

Chicago Manual of Style (16^{th} Edition):

Battermann, Astrid. “Preconditioning of Karush – Kuhn – Tucker Systems arising in Optimal Control Problems.” 1996. Masters Thesis, Virginia Tech. Accessed November 28, 2020. http://hdl.handle.net/10919/9579.

MLA Handbook (7^{th} Edition):

Battermann, Astrid. “Preconditioning of Karush – Kuhn – Tucker Systems arising in Optimal Control Problems.” 1996. Web. 28 Nov 2020.

Vancouver:

Battermann A. Preconditioning of Karush – Kuhn – Tucker Systems arising in Optimal Control Problems. [Internet] [Masters thesis]. Virginia Tech; 1996. [cited 2020 Nov 28]. Available from: http://hdl.handle.net/10919/9579.

Council of Science Editors:

Battermann A. Preconditioning of Karush – Kuhn – Tucker Systems arising in Optimal Control Problems. [Masters Thesis]. Virginia Tech; 1996. Available from: http://hdl.handle.net/10919/9579

University of South Florida

3. Van Nostrand, Caleb. A Discrete-Continuous Modeling Framework for Long-Distance, Leisure Travel Demand Analysis.

Degree: 2011, University of South Florida

URL: https://scholarcommons.usf.edu/etd/3389

This study contributes to the literature on national long-distance travel demand modeling by providing an analysis of households' annual destination choices and time allocation patterns for long-distance leisure travel purposes. An annual vacation destination choice and time allocation model is formulated to simultaneously predict the different destinations that a household visits and the time it spends on each of these visited destinations, in a year. The model takes the form of a Multiple Discrete-Continuous Extreme Value (MDCEV) structure (Bhat, 2005; Bhat, 2008). The model assumes that households allocate their annual vacation time to visit one or more destinations in a year to maximize the utility derived from their choices. The model framework accommodates variety-seeking in households' vacation destination choices in that households can potentially visit a variety of destinations rather than spending all of their annual vacation time for visiting a single destination. At the same time, the model accommodates corner solutions to recognize that households may not necessarily visit all available destinations. An annual vacation time budget is also considered to recognize that households may operate under time budget constraints. Further, the paper proposes a variant of the MDCEV model that avoids the prediction of unrealistically small amounts of time allocation to the chosen alternatives. To do so, the continuously non-linear utility functional form in the MDCEV framework is replaced with a combination of a linear and non-linear form.
The empirical data for this analysis comes from the 1995 American Travel Survey Data, with the U.S. divided into 210 alternative destinations. The empirical analysis provides important insights into the determinants of households' leisure destination choice and time allocation patterns.
An appealing feature of the proposed model is its applicability in a national, long-distance leisure travel demand model system. The annual destination choices and time allocations predicted by this model can be used for subsequent analysis of the number of trips made (in a year) to each destination and the travel choices for each trip. The outputs from such a national travel modeling framework can be used to obtain national-level Origin-Destination demand tables for long-distance leisure travel.

Subjects/Keywords: Destination Choice; Kuhn-Tucker Demand Model Systems; Long Distance Travel; National Travel Model; Vacation Travel Demand; American Studies; Arts and Humanities; Civil Engineering; Urban Studies and Planning

Record Details Similar Records

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^{th} Edition):

Van Nostrand, C. (2011). A Discrete-Continuous Modeling Framework for Long-Distance, Leisure Travel Demand Analysis. (Thesis). University of South Florida. Retrieved from https://scholarcommons.usf.edu/etd/3389

Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^{th} Edition):

Van Nostrand, Caleb. “A Discrete-Continuous Modeling Framework for Long-Distance, Leisure Travel Demand Analysis.” 2011. Thesis, University of South Florida. Accessed November 28, 2020. https://scholarcommons.usf.edu/etd/3389.

Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^{th} Edition):

Van Nostrand, Caleb. “A Discrete-Continuous Modeling Framework for Long-Distance, Leisure Travel Demand Analysis.” 2011. Web. 28 Nov 2020.

Vancouver:

Van Nostrand C. A Discrete-Continuous Modeling Framework for Long-Distance, Leisure Travel Demand Analysis. [Internet] [Thesis]. University of South Florida; 2011. [cited 2020 Nov 28]. Available from: https://scholarcommons.usf.edu/etd/3389.

Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Van Nostrand C. A Discrete-Continuous Modeling Framework for Long-Distance, Leisure Travel Demand Analysis. [Thesis]. University of South Florida; 2011. Available from: https://scholarcommons.usf.edu/etd/3389

Not specified: Masters Thesis or Doctoral Dissertation