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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.
91

A Top-Down, Hierarchical, System-of-Systems Approach to the Design of an Air Defense Weapon

Ender, Tommer Rafael 07 July 2006 (has links)
Systems engineering introduces the notion of top-down design, which involves viewing an entire system comprised of its components as a whole functioning unit. This requires an understanding of how those components efficiently interact, with optimization of the process emphasized rather than solely focusing on micro-level system components. The traditional approach to the systems engineering process involves requirements decomposition and flow down across a hierarchy of decision making levels, in which needs and requirements at one level are transformed into a set of system product and process descriptions for the next lower level. This top-down requirements flow approach therefore requires an iterative process between adjacent levels to verify that the design solution satisfies the requirements, with no direct flow between nonadjacent hierarchy levels. This thesis introduces a methodology that enables decision makers anywhere across a system-of-systems hierarchy to rapidly and simultaneously manipulate the design space, however complex. A hierarchical decision making process will be developed in which a system-of-systems, or multiple operationally and managerially independent systems, interact to affect a series of top level metrics. This takes the notion of top-down requirements flow one step further to allow for simultaneous bottom-up and top-down design, enabled by the use of neural network surrogate models to represent the complex design space. Using a proof-of-concept case study of employing a guided projectile for mortar interception, this process will show how the iterative steps that are usually required when dealing with flowing requirements from one level to the next lower in the systems engineering process are eliminated, allowing for direct manipulation across nonadjacent levels in the hierarchy. For this system-of-systems environment comprised of a Monte Carlo based design space exploration employing rapid neural network surrogate models, both bottom-up and top-down design analysis may be executed simultaneously. This process enables any response to be treated as an independent variable, meaning that information can flow in either direction within the hierarchy.
92

A Three-level Hierarchical Location-allocation Model For Regional Organization Of Perinatal Care

Karakaya, Sakir 01 February 2008 (has links) (PDF)
While the concept of regional organization (regionalization) of perinatal care aimed at reducing perinatal mortality has remained at the agenda of developed countries since 1970&rsquo / s, Turkey is one of the countries that does not have such a system yet. In this study, a three-level hierarchical location-allocation model is developed for the regionalization of perinatal care in an attempt to have a better distribution of maternal and perinatal health care services in Turkey. Since the mathematical model developed is difficult to solve in a reasonable time, we propose three heuristic approaches: top-down, modified top-down and Lagrangean relaxation based heuristics. These heuristics are computationally tested on a set of problem instances for networks ranging from 10 to 737 vertices. A significant result is that Lagrangean relaxation based heuristic outperforms the other two heuristics in terms of solution quality. In most of the test problems, the modified top-down heuristic outperforms the top-down heuristic in terms of solution quality. Using the proposed approaches, we solve a real life problem corresponding to the Eastern and South Eastern Anatolian Regions (the East Region) of Turkey.
93

Determining The Roles Of Water Level And Fish Predation On Submerged Plant Growth In Shallow Lakes Using Mesocosm Experiment

Tuba, Bucak 01 February 2011 (has links) (PDF)
Four-month mesocosm experiment from June 1st to September 25th, 2009, was conducted to determine the effect of water level dierence in combination with fish predation pressure, on submerged macrophyte development, in an eutrophic shallow lake. Effect of water level fluctuation was simulated by placing enclosures to the different water depths that included 0.8 m, 1.6 m and 2.3 m on Lake Eymir. These enclosures having a cylindirical shape and 1.2 m diameter, were open to sediment and atmosphere interaction. The highest water level mesocosms were cancelled after fifth sampling due to rapture in the bags, hence this thesis does not include the results of 2.3 m. At each depth, half of the enclosures were stocked with planktivo-omnivorous fish (Tinca tinca, Alburnus spp.) which are natural fauna of Lake Eymir. Before stocking of fish, ten shoots of Potamageton pectinatus were added to all of the enclosures in order to observe submerged macrophyte development. Sampling for physico-chemical parameters, zooplankton, chlorophyll a, PVI% and periphyton was conducted weekly for the first five weeks, last six samplings were done biweekly. Macrophyte harvesting for dry weight estimation was done at the end of the experiment. Throughout the experiment water level decreased 0.41 &plusmn / 0.06 m in each enclosures. Water level was so critical for macrophyte development that no significant macrophyte growth was observed in enclosures located at 1.6 m (HW). However, fish predation did not prevent the growth of macrophyte in enclosures located at 0.8 m (LW) but it was important in HW enclosure for affecting water clarity. Fish predation affected chlorophyll a, zooplankton and nutrient concentrations and the effect was mostly pronounced at LW enclosures. They had high chlorophyll a and nutrient concentrations but it did not repress macrophyte growth as in temperate lakes. Despite high water clarity in HW fishless enclosures, very low macrophyte biomass may be attributed to enhanced periphyton development. Zooplankton community shifted to small sized ones under fish predation while fishless enclosures had higher zooplankton /phytoplankton ratio for each depth. Hence, regarding these results it can be stated that decrease in water level can compensate the negative effects of fish predation on macrophyte growth in warm Mediterranean lakes.
94

Document Analysis and Recognition

WATANABE, Toyohide 20 March 1999 (has links)
No description available.
95

Konzeption eines Umweltkennzahlensystems zur Umweltleistungsmessung für Prozesse unter Beachtung der in Unternehmen vorliegenden Rahmenbedingungen

Scheibe, Lilly 09 January 2004 (has links) (PDF)
Die vorliegende Ausgabe beschäftigt sich mit dem Thema Umweltkennzahlensysteme für die Umweltleistungsmessung. Ziel der Arbeit ist es, Unternehmen ein Hilfsmittel zur Integration von Umweltaspekten ins allgemeine Unternehmensgeschehen an die Hand zu geben. Angestrebt ist die Konzeption eines Umweltkennzahlensystems zur Umweltleistungsmessung für Prozesse. Im ersten Schritt wird ein Öko-Controlling-Modell vorgestellt und Umweltkennzahlensysteme in dieses eingeordnet. Umweltkennzahlensysteme sind der Informationsversorgung zuzurechnen. Sie dienen der Information der Informationsverwender, die mit ihrer Hilfe Planen, Steuern und Kontrollieren sollen. Es wird ein Anforderungsprofil für Umweltkennzahlensysteme erstellt, dieses Anforderungsprofil beinhaltet allgemeine Anforderungen, wie die ?Anforderungen der Informationsverwender? und ?formale und logische Anforderungen? und spezielle Anforderungen. Vorhandene Ansätze zu Umweltkennzahlensystemen werden vorgestellt und hinsichtlich des Anforderungsprofils analysiert. Aus dieser Analyse ergibt sich der Schluss, dass es kein Umweltkennzahlensystem gibt, das alle Anforderungen erfüllt. Die Auswertung der an ausgewählte Führungskräfte der SIEMENS AG verschickten Fragebögen zu Umweltkennzahlen bestätigt die gewonnene Aussage der Nicht-Existenz einer first-best-Lösung hinsichtlich eines Umweltkennzahlensystems für alle Unternehmen, da sie verdeutlicht, dass schon die Kennzahlensysteme innerhalb eines Unternehmens stark (aufgrund zu unterschiedlicher Strukturen, Ziele und Strategien) differieren. An die Auswertung der Analyse der vorhandenen Ansätze und der Fragebögen schließt sich die Entwicklung einer Vorgehensweise zur Konzeption von Umweltkennzahlensystemen in Unternehmen an, die in den Schritten Festlegung der Umweltleistung von Unternehmen, Definition der Zielebene, Festlegung und Auswahl von Kennzahlen abläuft.
96

An fMRI Study on Context‐Dependent Processing of Natural Visual Scenes

Petzold, Antje 28 October 2009 (has links) (PDF)
Visual attention can be voluntarily focused on a location or automatically attracted by salient features in a visual scene. Studies using functional Magnetic Resonance Imaging (fMRI) suggest two networks of visual attention involved in these complementary mechanisms: a dorsal frontoparietal network and a ventral frontoparietal network of visuospatial attention respectively. However, most studies so far have applied non‐natural schematic stimuli. The present study investigates visual attention in images of natural environmental scenes. Adopting previously used eye‐tracker paradigms, we study the influence of task instruction and luminance contrast modifications in pictures on both eye movements and neural activity using Eye‐Tracking and functional Magnetic Resonance Imaging simultaneously. We expect increased top‐down control of attention in a search task compared to a free viewing condition visible in enhanced neural activation in the intraparietal sulcus (IPS) as part of the dorsal frontoparietal network. Strong modifications of luminance contrast should foster bottom‐up processing activating the temporoparietal junction (TPJ) a crucial area in the ventral frontoparietal network of visual attention. Although the obtained eye‐tracking data shows the expected shift of fixations towards locations of increased luminance contrast, we do not find an influence of luminance contrast modifications on neural processing. Comparison of instructions reveals diverse results across participants possibly due to the long presentation duration of stimuli which allowed participant’s attention to wander independently of task instruction. We find bilateral activation in IPS and parahippocampal place area (PPA) as well as bilateral deactivation in the TPJ region independent of task context. This might indicate similar contributions of these areas to free viewing of and search in visual scenes. However, dissociation of target detection and attention during search by deconvolution analysis of data obtained in this study might reveal a more detailed picture of functional involvement of the IPS and TPJ region in processes of visual attention. Remarkably, results show robust activation of the PPA in both tasks, suggesting that the PPA region might not only be activated by houses and open scenes but by narrow scenes (bushes, leaves) of natural outdoor environment as well.
97

Leading learning through imposition of leadership learning standards [electronic resource] / by Raymond D. Jorgensen.

Jorgensen, Raymond D. January 2003 (has links)
Title from PDF of title page. / Document formatted into pages; contains 185 pages. / Thesis (Ph.D.)--University of South Florida, 2003. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: This study explored the impact of an imposed standards movement on attitudes and behaviors of a team of line leaders. A case method was employed to describe, to explain, and to draw conclusions about results of standards imposition. Standards were designed and implemented by an executive leadership team frustrated with lack of effective leadership practices of a line leaders team under their supervision. The investigation took an historical perspective, chronicling the story of the company, emerging leadership challenges, and executive leadership responses leading up to the research. The line or team leaders of an educational software company served as participants. Data were archival, gathered through consultation via focus groups, interviews, questionnaires, and fieldwork journal notes. Verbatim responses to protocols were used as evidence of leadership practices. / ABSTRACT: The structure of leading in professional communities espoused by Senge, Greenleaf, Bennis, Kouzes, Posner, and others informed data analysis of team leaders' responses to imposed standards. Results revealed six themes: Positive Attitude toward Learning; Positive Attitude toward Peer Learning Groups; Increased Skill, Performance, Satisfaction, and Confidence resulting from imposed standards; Shift from Negative Attitude toward Change; team leaders' Commitment to Imposed Goals as a work requirement; and Loss of Advantages Gained from Standards Imposition over time due to removal of the learning requirement. This research adds to the literature available for leaders in relation to designing responses to emergent resistance toward accomplishing imposed standards. Team leaders identified the learner ethic as a leadership attribute crystallized by the standards imposition movement. / ABSTRACT: Although leaders believed in learning, they developed heightened awareness regarding the importance of learning as a survival tactic for themselves and the company. / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.
98

Leading learning through imposition of leadership learning standards

Jorgensen, Raymond D. 01 January 2003 (has links)
This study explored the impact of an imposed standards movement on attitudes and behaviors of a team of line leaders. A case method was employed to describe, to explain, and to draw conclusions about results of standards imposition. Standards were designed and implemented by an executive leadership team frustrated with lack of effective leadership practices of a line leaders team under their supervision. The investigation took an historical perspective, chronicling the story of the company, emerging leadership challenges, and executive leadership responses leading up to the research. The line or team leaders of an educational software company served as participants. Data were archival, gathered through consultation via focus groups, interviews, questionnaires, and fieldwork journal notes. Verbatim responses to protocols were used as evidence of leadership practices. The structure of leading in professional communities espoused by Senge, Greenleaf, Bennis, Kouzes, Posner, and others informed data analysis of team leaders' responses to imposed standards. Results revealed six themes: Positive Attitude toward Learning; Positive Attitude toward Peer Learning Groups; Increased Skill, Performance, Satisfaction, and Confidence resulting from imposed standards; Shift from Negative Attitude toward Change; team leaders' Commitment to Imposed Goals as a work requirement; and Loss of Advantages Gained from Standards Imposition over time due to removal of the learning requirement. This research adds to the literature available for leaders in relation to designing responses to emergent resistance toward accomplishing imposed standards. Team leaders identified the learner ethic as a leadership attribute crystallized by the standards imposition movement.
99

Development of tandem mass spectrometric methods for proteome analysis utilizing photodissociation and ion/ion reactions

Shaw, Jared Bryan 13 September 2013 (has links)
The utility of 193 nm ultraviolet photodissociation (UVPD) and negative electron transfer dissociation (NETD) for the characterization of peptide anions was systematically evaluated. UVPD outperformed NETD in nearly all metrics; however, both methods provided complementary information to traditional collision induced dissociation (CID) of peptide cations in high throughput analyses. In order to enhance the performance of NETD, activated ion negative electron transfer dissociation (AI-NETD) methods were developed and characterized. The use of low-level infrared photoactivation or collisional activation during the NETD reaction period significantly improved peptide anion sequencing capabilities compared to NETD alone. Tyrosine deprotonation was shown to yield preferential electron detachment upon NETD or UVPD, resulting in N - C[alpha] bond cleavage N-terminal to the tyrosine residue. LC-MS/MS analysis of a tryptic digest of BSA demonstrated that these cleavages were regularly observed under high pH conditions. Transmission mode desorption electrospray ionization (TM-DESI) was coupled with 193 nm UVPD and CID for the rapid analysis and identification of protein digests. Comparative results are presented for TM-DESI-MS/CID and TM-DESI-MS/UVPD analyses of five proteolyzed model proteins. In some cases TM-DESI/UVPD outperformed TM-DESI-MS/CID due to the production of an extensive array of sequence ions and the ability to detect low m/z product ions. 193 nm UVPD was implemented in an Orbitrap mass spectrometer for characterization of intact proteins. Near-complete fragmentation of proteins up to 29 kDa was achieved. The high-energy activation afforded by UVPD exhibited far less precursor ion charge state dependence than conventional methods, and the viability of 193 nm UVPD for high throughput top-down proteomics analyses was demonstrated for the less 30 kDa protein from a fractionated yeast cell lysate. The use of helium instead of nitrogen as the C-trap and HCD cell bath gas and trapping ions in the HCD cell prior to high resolution mass analysis significantly reduced the signal decay rate for large protein ions. As a result, monoclonal IgG1 antibody was isotopically resolved and mass accurately determined. A new high mass record for which accurate mass and isotopic resolution has been achieved (148,706.3391 Da ± 3.1 ppm) was established. / text
100

The 4 Disciplines of Execution - revolutionerande styrningsmetod eller onödigt substitut?

Frislund, Andreas, Ågrup, Gustav January 2015 (has links)
Problem: Då omvärlden är under ständig förändring behöver organisationer anpassa sig med nya strategier, mål och styrningsmetoder för att överleva. FranklinCovey har nyligen tagit fram ett, enligt dem, nytt och revolutionerande styrningsverktyg som kommer styra team och organisationer framåt. Kan detta vara nästa stora teori inom ekonomistyrning? Syfte: Uppsatsen syfte är att kritiskt och empiriskt redogöra för samt analysera ”The 4 Disciplines of Execution” som styrningsverktyg i organisationer. Vidare ämnar studien undersöka om metoden är ett värdeskapande instrument eller enbart ett likvärdigt substitut till existerande och mer etablerade styrningsteorier. Metod: Studien är en kvalitativ enfallsstudie av deskriptiv och explorativ karaktär. Undersökningen har präglats av en induktiv ansats där semi-strukturerade intervjuer på Atea AB stått till grund för studiens resultat. Vidare analyserades resultatet med hjälp av Otleys ramverk för utvärdering av management control systems. Resultat: Studien visar att ”The 4 Discplines of Execution inte är något revolutionerande men likväl ett värdefullt komplement till ekonomistyrning. Då verktyget fokuserar på förändringsprocessen i beteendet hos medarbetare och involverar hela organisationen från företagsledning till individnivå, är det användbart i dagens miljö som ständigt förändras.

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