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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.
321

Characterizing the Construct of Organizational Unity of Effort In the Interagency National Security Policy Process

Severance, Paul Michael 24 June 2005 (has links)
The sea state changes that have occurred in the global security arena since the fall of the Berlin Wall and the demise of the Soviet Union dramatically transformed the U.S. interagency national security process. More recently, the tragic events of 9-11 have further refocused national security endeavors inward to homeland security imperatives while Operations Enduring Freedom and Iraqi Freedom have revalidated the need effective interagency coordination. This research represents a "first cut" at characterizing the construct of unity of effort in the interagency national security process by identifying attributes of this organizational virtue. The intent was to examine the dimensionality of the construct and thus facilitate theory building by consolidating extant knowledge and identifying key success factors as well as elements threatening operational success. This study focused on the interagency national security policy process and was intended to accommodate a wider understanding of unity of effort as it applies to that area of endeavor. Multiple interviews, focus groups, and surveys from 448 military and civilian adult respondents were used in the analysis. Content analysis, analysis of variance, and principle component analysis were the primary analytic methods used. The most conceptually sound factor structure for organizational unity of effort consisted of four factors: (a) Organizational Context and Interpersonal Dynamics, (b) Leadership and Decision Making Structure, (c) Strategic Orientation, and (d) Organizational Infrastructure and Resources. The detailed examination of this construct produced clearly acceptable internal reliability coefficients on all scales and relatively strong evidence of construct validity in the related factor analyses. Separate internal factor structures were investigated for two test groups drawn from the sample population. Although there was not perfect fidelity in the two derived factor structures, sufficient internal structures emerged that strongly validated the underlying factor structure for organizational unity of effort. This factor structure remained relatively stable when examined for selected demographic sub-groups drawn from the larger sample. The clear relationships of this factor construct revealed strong empirical support for a theoretical basis for the construct of organizational unity of effort. Moreover, the results of this study offer the potential for development of a simple and valid conceptualization of organizational unity of effort. It is hoped that this research serves to advance a conceptual framework that helps the interagency national security community evaluate unity of effort in the national security policy process and create new or reconfigure existing organizational entities in response to threats to U.S. national security. / Ph. D.
322

Learning, Game Play, and Convergence of Behavior in Evolving Social Networks

Pan, Zhengzheng 28 May 2009 (has links)
I study information dissemination and opinion formation in a framework of evolving social networks. Individuals take weighted averages repeatedly to update their opinions. They also update their assessments on others' opinions, represented by an influence weight matrix. It is proven that both opinions and the influence weights are convergent. In the steady state, consensus is reached where all individuals hold the same opinion. Convergence occurs with an extended model as well, which indicates the tremendous influential power possessed by a minority group. Then I impose a dual network structure, where individuals not only collect information, but also use the information to play a coordination game with a selected group of opponents that one is connected with. All individuals update their strategies based on a naive learning process within a separate influence network in which information is disseminated. The selection of opponents also gets updated over time. I calculate the critical values of costs associated with connections for different network structures and strategies to occur in the steady state. Finally, I investigate the outcomes of social learning under various exogenous network structures. Individuals use an algorithm that takes into account both proximity of opinions and impact of neighbors. Results also show consensus, with convergence speed correlated with the network structure. In addition, an endogenous network formation in two stages that utilizes network and distance between agents' opinions is proposed. The resulting networks show power-law patterns in degree distribution. / Ph. D.
323

Parenting Coordinators' Practices Recommendations: A Qualitative Study

Hirsch, Barbara Phyllis 01 July 2016 (has links)
This qualitative study used a phenomenological approach to understand the experiences of seven parenting coordinators in using parenting coordination practices that they have found to be effective and would recommend to other parenting coordinators to achieve the following goals: educating parents, increasing the quality of parenting and co-parenting, managing conflict, and involving children and other family members in the process of parenting coordination. Data were collected with semi-structured interviews and analyzed using thematic coding. Initial findings suggest that there exists useful practice techniques toward achieving these goals, and supports a practice model informed by the evaluation by parenting coordinators of the efficacy of their chosen methods in the context of their practices. Participants report promoting cooperative co-parenting, stress parental autonomy, and supported parental decision making over parenting coordinator recommendations. Practical implications are discussed. / Master of Science
324

Framing Coordination in Collocated Computer-Mediated Communication

Alaloula, Nouf M. 26 May 2010 (has links)
This thesis explores the framing of coordinative experience in collocated computer-mediated communication. It highlights the importance of low- level coordinative properties through multifaceted examination of the transcript of the first minute of a constructed coordinative situation. In efforts to truly understand the culture we are creating and invoking by adding computers to people's activities in groups, and life in general. A lab study was conducted using a computer program that allows one or more users to solve a Sudoku puzzle together, each on their own separate computer. This allowed for an investigation of what happens when people and technology are located in the same place. How do people construct their situation, in terms of who goes next, what do they do and what constitutes the behavior framing. / Master of Science
325

Strategic Alliances in Beef: Concepts and Design

Hudson, William Taylor 31 January 2001 (has links)
Alliances between participants in the beef industry have developed rapidly during the past 10 years. Industry surveys reveal alliances are expected to grow larger in number and become a more dominant part of the beef sector over the next 10 years. This research centers on providing design specific information to managers and decision makers involved with creating alliance organizations, thereby improving the likelihood of future alliance success. A conceptual framework was created to better understand the process of alliance formation. Each participant in the alliance first prioritizes economic motivations for joining, creates unique governance structure designs reflecting motivations, and then assesses results to decide on future participation. Simulations were performed using empirical data from a private beef alliance to analyze various margin sharing and premium allocation designs. Cattle owners were found to prefer equal margin sharing, while packers would prefer to accept a transfer of cattle owner margins rather than share packing margins with owners. Premiums were found to be substantial for cattle grading higher than a Choice YG3 quality level. Premiums averaged $12/head, $8/head, and $4/head when 75%, 50%, and 25% of cattle qualified for premium lines, respectively. Premium rights were found to be good substitutes for equal margin sharing agreements, allowing packers to accept equal margin sharing agreements while maintaining an equivalent level of return from premium rights. Marginal rates of substitution between changes in premium rights and changes in equal margin sharing levels are identified, allowing for more informed negotiations between cattle owners and packers. / Master of Science
326

Development and evaluation of methods for structured recording of heart murmur findings using SNOMED CT® post-coordination

Green, Julie Meadows 20 December 2004 (has links)
Objective: Structured recording of examination findings, such as heart murmurs, is important for effective retrieval and analysis of data. Our study proposes two models for post-coordinating murmur findings and evaluates their ability to record murmurs found in clinical records. Methods: Two models were proposed for post-coordinating murmur findings: the Concept-dependent Attributes model and the Interprets/Has interpretation model. A micro-nomenclature was created based on each model by using the subset and extension mechanisms provided for by the SNOMED-CT® framework. Within each micro-nomenclature a partonomy of cardiac cycle timing values was generated. In order for each model to be capable of representing clinical data, a mechanism for handling range values was developed. One hundred murmurs taken from clinical records were entered into two systems that were built based on each model to enter and display murmur data. Results: Both models were able to record all 100 murmur findings; both required the addition of the same number of concepts into their respective micro-nomenclatures. However, the Interprets/Has interpretation model required twice the storage space for recording murmurs. Conclusion: We found little difference in the requirements for implementation of either model. In fact, data stored using these models could be easily inter-converted. This will allow system developers to choose a model based on their own preferences. If at a later date a method is chosen for modeling within SNOMED-CT, the data can be converted to conform if necessary. / Master of Science
327

Effets d’une hyperbilirubinémie modérée sur la physiologie de la déglutition nutritive et de la coordination déglutition-respiration chez l’agneau prématuré / Effect of moderate hyperbilirubinemia on nutritive swallowing and swallowing-breathing coordination in the preterm lamb

Bourgoin-Heck, Mélisande January 2016 (has links)
Résumé : L’ictère néonatal, lié à l’hyperbilirubinémie, touche 90% des nouveau-nés prématurés. L’hyperbilirubinémie provoque des troubles neurologiques aigus (somnolence, dystonie, difficultés alimentaires, atteinte de l’audition) et a été reliée à des anomalies du contrôle respiratoire. Ces résultats suggèrent une neurotoxicité de la bilirubine sur le tronc cérébral, qui pourrait aussi affecter les centres déglutiteurs. Le but de cette étude est de tester notre hypothèse selon laquelle l’hyperbilirubinémie altère la déglutition nutritive et la coordination déglutition-respiration chez l’agneau prématuré. 11 agneaux prématurés (nés 14 jours avant terme) ont été randomisés dans un groupe contrôle (n = 6) et un groupe bilirubine (n = 5). À 5 jours de vie, une hyperbilirubinémie modérée (150-250 μmol/L) était induite pendant 17h chez les agneaux du groupe bilirubine. La déglutition était étudiée par l’enregistrement de la pression pharyngée, et la respiration était évaluée par pléthysmographie d’inductance respiratoire et oxymétrie de pouls. L’effet de l’hyperbilirubinémie sur la déglutition nutritive (DN) était évalué pendant une alimentation au biberon standardisée, avec du lait de brebis. Un second enregistrement était réalisé 48h plus tard, après normalisation de la bilirubine. L’alimentation était moins performante (mL/min) dans le groupe bilirubine (p = 0,002) avec des DN moins fréquentes (p = 0,003) et de plus petit volume (p = 0,01). Ces différences n’étaient pas retrouvées à distance de l’hyperbilirubinémie. La coordination déglutition-respiration était également altérée chez les agneaux du groupe bilirubine, indiquée par une tendance à la diminution de la durée de l’inhibition respiratoire pendant les bouffées de DN (p < 0,1), ceci pendant et après l’hyperbilirubinémie. Simultanément, pendant l’alimentation, les agneaux du groupe bilirubine passaient plus de temps en désaturations sévère (< 80%) que ceux du groupe contrôle. Enfin, une diminution de la fréquence respiratoire associée à une augmentation des apnées étaient observées dans les minutes suivant l’alimentation dans le groupe bilirubine (p < 0,05). La déglutition et la coordination déglutition-respiration sont altérées par l’hyperbilirubinémie modérée, chez l’agneau prématuré. La diminution globale d’efficacité de l’alimentation au biberon est associée à une poursuite de la respiration durant les bouffées de DN, ce qui pourrait favoriser les aspirations pulmonaires de lait. / Abstract : Rationale: Jaundice, secondary to hyperbilirubinemia (HB), develops in 90% of preterm newborns. HB induces acute neurological disorders (somnolence, abnormal tone, feeding difficulties, auditory dysfunction) and has been linked to alterations in respiratory control. These findings suggest neurotoxicity in the brainstem that could also affect swallowing centers. This study aims to test our hypothesis that HB impairs nutritive swallowing and swallowing‐breathing coordination in the preterm lamb. Methods: Two groups of preterm lambs (born 14 days prior to term), control (C, n = 6) and hyperbilirubinemia (HB, n = 5) were studied. At day 5 of life, moderate HB (150‐250 μmol/L) was induced during 17 h in HB lambs. Swallowing was assessed via recording of pharyngeal pressure, and respiration was studied by respiratory inductance plethysmography and pulsed oximetry. HB effect on nutritive swallowing was assessed during standardized bottle‐feeding with ewe milk. A second recording was performed 48 hours later, after recovery from hyperbilirubinemia. Results: Swallows were less frequent (p = 0.003) and of smaller volume (p = 0.01) in HB lambs, with a consequent decrease in minute swallowing in HB lambs (p = 0,004). These differences were not found after bilirubinemia was returned to normal. Swallowing‐breathing coordination was also impaired in HB lambs, as indicated by a tendency towards a decrease in % time with respiratory inhibition during bursts of swallows, during and after hyperbilirubinemia. Simultaneously, severe desaturations (< 80%) were longer in HB lambs than in C lambs. Finally, a decreased respiratory rate was observed immediately after feeding (p < 0,05), along with increased apneas duration. Conclusions: Both swallowing and swallowing‐breathing coordination are altered by acute, moderate HB in preterm lambs. The overall decreased efficiency at bottle‐feeding is accompanied by continuation of breathing during bursts of swallows, which may promote lung aspiration.
328

Imine-donor complexes with group 6 and group 11 transition metals : coordination and dynamics

De Jongh, Leigh-Anne 12 1900 (has links)
Thesis (MSc (Chemistry and Polymer Science))--Stellenbosch University, 2008. / In this study the coordination of ligands with several coordination sites, 2-aminoazoles (2- amino-4-methylthiazole), 2-aminobenzothiazole, 2-aminobenzoimidazole and 2- aminothiazoline and a biguanidine (N-(2-methylphenyl)imidodicarbonimidic diamide) to soft metal centres [gold(I) (group 11), chromium(0) (group 6) and tungsten (0) (group 6)] was investigated. The aminoazoles have three coordination sites, an exocyclic amine nitrogen, an endocyclic imine nitrogen and an endocyclic thioether sulphur. The biguanidine ligand has three sites for deprotonation, one central amine and two imine nitrogens, and at least five sites available for nitrogen coordination.
329

Novel metal organic frameworks : synthesis, characterisation and functions

Haja Mohideen, Mohamed Infas January 2011 (has links)
The synthesis and properties of novel Metal Organic Frameworks were investigated and reported in this thesis. Thirteen new materials have been synthesized and their properties have been discussed with nine of the structures being solved. The most interesting and useful MOF among the thirteen materials is STAM-1, a copper-based Metal Organic Framework in which the starting linker (Benzene-1,3,5-tricarboxylic acid) undergoes selective in situ monoesterification during the synthesis. The monoesterified BTC can be recovered easily from the MOF, opening up MOF synthesis as a “protection” tool for unexpected selectivity in preparative chemistry that is difficult to accomplish using standard organic chemistry approaches. The selective linker derivatisation leads to the formation of a porous MOF with two types of accessible channel; one hydrophilic lined by copper and the other hydrophobic, lined by the ester groups. The unique structure of the pores leads to unprecedented adsorption behaviour, which reacts differently to gases or vapours of dissimilar chemistry and allows them to access different parts of the structure. The structural flexibility of STAM-1 shows significant differences in the kinetics of O₂ and N₂ adsorption, showing potential for new materials to be developed for air separation. Having two types of channel systems, adsorption can be switched between the two channels by judicious choice of the conditions; a thermal trigger to open the hydrophilic channel and a chemical trigger to open the hydrophobic channel. The storage and release capability of NO in STAM-1 was investigated for use in biomedical applications. Successful studies showed the strength of the antibacterial effects of NO loaded STAM-1, by using three different bacterial strains as a test of performance and were found to be bactericidal. Furthermore the antibacterial effects of NO free STAM-1 were also probed and found to be bactericidal even with low concentrations of the material such as 5 wt%. STAM-1 showed some complex magnetic behaviour by displaying strong antiferromagnetic properties at room temperature and ferromagnetic properties at lower temperatures. The antiferromagnetic coupling was observed within the dimer and ferromagnetic coupling between the dimers. This property of ferromagnetism can only be attributed to the corporation of magnetic dimers in the framework. STAM-2 displays a different magnetic behaviour than STAM-1 which shows paramagnetic properties at room temperature and antiferromagnetic properties at lower temperatures. Other novel MOFs were also successfully characterised and their properties were investigated for potential applications.
330

Nouveaux ligands mixtes phosphorés: synthèse, coordination et étude de réactivité

Payet, Elina 26 November 2010 (has links) (PDF)
Au cours de ce travail de thèse, la synthèse de nouveaux ligands mixtes combinant des fonctions de propriétés électroniques différentes (phosphores, amines, alcène, amidure, iminophosphorane) a été abordée. Leur chimie de coordination a été étudiée et certains complexes isolés ont été utilisés en catalyse (oligomérisation d'éthylène, hydrogénation par transfert d'hydrure).

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