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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Innovation and technology trajectories in a developing country context: evidence from a survey of Malaysian firms

Hegde, Deepak 12 April 2004 (has links)
This thesis investigates the relevance of currently used firm-level innovation concepts in a developing country context. I draw on the results of a comprehensive survey of manufacturing and service firms instrumented to assess the knowledge- capabilities of the economic sectors in Malaysia. The thesis presents a discussion of the extant literature on firm-level innovation and tests hypotheses regarding the impact of firms organizational structure, strategies, resources and environment as determinants of product, process and organizational innovations. These are examined from the classifying framework provided by Keith Pavitts model of technology trajectories to better understand the nature of innovation and its production determinants. I find that Malaysian firms -- across all sectors -- show a greater propensity to make process and organizational innovations as against product innovations. Soft factors like training, knowledge management practices and collaboration with market actors are used as significant inputs in their innovation process.
82

The Characteristics of Solitary Wave in Lagrangian System

Lin, Chu-yu 28 July 2011 (has links)
As a solitary wave is usually used to characterize the behavior of a tsunami, a hydraulic experiment is set up for a detailed study of the associated celerity and particle trajectory. The size of the water tank of this experiment in this paper is 21m long, 0.5m width and 0.7m deep. Wave maker method used by Goring (1978) for simulating Solitary Waves is applied in the experiment of particle trajectories and mass transport. We also extend the particle trajectories theory to higher order that contains the non-linear terms. The method presented in this paper fixes the position of the camera, and the grid-point board is located in the center of the water tank, so that the particle and the two-dimensional grid surface coincide. Then, we analyze the particle trajectories within the grid with image processing techniques. This method not only save time of coordinate calibration, but also get a more accurate measurement. The water particle used in this paper has 1mm diameter, because it is difficult to locate the exact position of a large particle. Because of the small size in this experiment, we can get better results and the error is reduced. To compare with the experiment, the third-order Eulerian solution of Feton(1972) is transferred to the Lagrangian system in the present study to get the particle velocity. Then an integral with respect to time is used to obtain the trajectory. The accuracy of the theory is good, especially in the regime of small amplitude. For large wave amplitude in terms of the water depth, a higher order solution is suggested for the future study.
83

Systematic examination of dynamically driven organic reactions via kinetic isotope effects

Ussing, Bryson Richard 25 April 2007 (has links)
Organic reactions are systematically examined experimentally and theoretically to determine the role dynamics plays in the outcome of the reaction. It is shown that trajectory studies are of vital importance in understanding reactions influenced by dynamical motion. This dissertation discusses how a combination of kinetic isotope effects, theoretical calculations, and quasiclassical dynamics trajectories aid in the understanding of the solvolysis of p-tolyldiazonium cation in water, the cycloadditions of cyclopentadiene with diphenylketene and dichloroketene, and the cycloaddition of 2- methyl-2-butene with dichloroketene. In the solvolysis of p-tolyldiazonium cation, significant 13C kinetic isotope effects are qualitatively consistent with a transition state leading to formation of an aryl cation, but on a quantitative basis, the isotope effects are not adequately accounted for by simple SN1 heterolysis to the aryl cation. The best predictions of the 13C isotope effects for the heterolytic process arise from transition structures solvated by clusters of water molecules. Dynamic trajectories starting from these transition structures afford products very slowly. The nucleophilic displacement process for aryldiazonium ions in water is determined to be at the boundary of the SN2Ar and SN1 mechanisms. The reaction of cyclopentadiene with diphenylketene affords both [4 + 2] and [2 + 2] cycloadducts directly. This is surprising. There is only one low-energy transition structure for adduct formation. Investigation of this reaction indicates that quasiclassical trajectories started from a single transition structure afford both [4 + 2] and [2 + 2] products. Overall, an understanding of the products, rates, selectivities, isotope effects, and mechanism in these reactions requires the explicit consideration of dynamic trajectories.
84

Quantum dynamics on adaptive grids : the moving boundary truncation method

Pettey, Lucas Richard, 1974- 11 October 2012 (has links)
A novel method for integrating the time-dependent Schrödinger equation is presented. The moving boundary truncation (MBT) method is a time-dependent adaptive method that can significantly reduce the number of grid points needed to perform accurate wave packet propagation while maintaining stability. Hydrodynamic quantum trajectories are used to adaptively define the boundaries and boundary conditions of a fixed grid. The result is a significant reduction in the number of grid points needed to perform accurate calculations. A variety of model potential energy surfaces are used to evaluate the method. Excellent agreement with fixed boundary grids was obtained for each example. By moving only the boundary points, stability was increased to the level of the full fixed grid. Variations of the MBT method are developed which allow it to be applied to any potential energy surface and used with any propagation method. A variation of MBT is applied to the collinear H+H₂ reaction (using a LEPS potential) to demonstrate the stability and accuracy. Reaction probabilities are calculated for the three dimensional non-rotating O(³P)+H₂ and O(³P)+HD reactions to demonstrate that the MBT can be used with a variety of numerical propagation techniques. / text
85

Reducing spacecraft state uncertainty through indirect trajectory optimization

Zimmer, Scott Jason 28 August 2008 (has links)
Not available / text
86

Temperament, parenting, and the development of childhood obesity

Hejazi, Samar 05 1900 (has links)
The purpose of this study was two-fold: (a) to identify, in a large representative sample of Canadian children, the age-related trajectories of overweight and obesity from toddlerhood into childhood and (b) to investigate the associations between these trajectories and children’s temperaments, their parents’ parenting practices and their interactions. Potentially important familial characteristics (i.e., the parents’ or surrogates’ age, income level, and educational attainment) were considered in the models. The sample for this study was drawn from the Canadian National Longitudinal Survey of Children and Youth (NLSCY). Group-based mixture modeling analyses were conducted to identify the number and types of distinct trajectories in the development of obesity (i.e., to explicate the developmental processes in the variability of childhood obesity) in a representative sample of children who were between 24 to 35 months of age, at baseline, and followed biennially over a 6-year span. Discriminant analysis was conducted to assess the theoretical notion of goodness-of-fit between parenting practices and children’s temperament, and their association with membership in the BMI trajectory groups. The results of the group-based modeling established three different BMI trajectories for the boys, namely: stable-normal BMI, transient-high BMI, and j-curve obesity. The analyses revealed four different trajectories of BMI change for the girls: stable-normal BMI, early-declining BMI, late-declining BMI, and accelerating rise to obesity. The multivariate analysis revealed that the combined predictors of the obesity trajectories of the girls (group membership) included having a fussy temperament, ineffective parenting, and parents’ educational attainment. Predictors of the boys’ obesity trajectory (group membership) included household income, parental education, and effective parenting practices. Understanding the different ways in which a child may develop obesity will allow nurses and other health professionals to take different approaches in the assessment, intervention and evaluation of obesity and obesity-related health problems. The results of this study further our understanding of factors associated with the development of obesity at a young age and hence may inform the development of early preventive programs.
87

Duality and multiparticle production.

Gordon, Earl Mark. January 1972 (has links)
No description available.
88

Complex quantum trajectories for barrier scattering

Rowland, Bradley Allen, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
89

Assessment of a space shuttle trajectory evaluation system (DOLILU II)

Chakravarthy, Diwakar. January 2000 (has links)
Thesis (M.S.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains vii, 105 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 76-79).
90

Quantum dynamics on adaptive grids the moving boundary truncation method /

Pettey, Lucas Richard, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.

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