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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.
21

Studies in macroeconomic dynamics

Rendu, Christel January 2000 (has links)
No description available.
22

Normalization of Process Safety Metrics

Wang, Mengtian 2012 August 1900 (has links)
This study is aimed at exploring new process safety metrics for measuring the process safety performance in processing industries. Following a series of catastrophic incidents such as the Bhopal chemical tragedy (1984) and Phillips 66 explosion (1989), process safety became a more important subject than ever. These incidents triggered the development and promulgation of the Process Safety Management (PSM) standard in 1992. While PSM enables management to optimize their process safety programs and organizational risks, there is an emerging need to evaluate the process safety implementation across an organization through measurements. Thus, the process safety metric is applied as a powerful tool that measures safety activities, status, and performance within PSM. In this study, process safety lagging metrics were introduced to describe the contribution of process related parameters in determining the safety performance of an organization. Lagging metrics take process safety incidents as the numerator and divide it by different process-related denominators. Currently a process lagging metric (uses work hours as denominator) introduced by the Center for Chemical Process Safety (CCPS) has been used to evaluate the safety performance in processing industries. However, this lagging metric doesn't include enough process safety information. Therefore, modified denominators are proposed in this study and compared with the existing time-based denominator to validate the effectiveness and applicability of the new metrics. Each proposed metric was validated using available industry data. Statistical unitization method has converted incident rates of different ranges for the convenience of comparison. Trend line analysis was the key indication for determining the appropriateness of new metrics. Results showed that some proposed process-related metrics have the potential as alternatives, along with the time-based metric, to evaluate process safety performance within organizations.
23

Impact of leading-edge orientation and shape on performance of a compressor blade /

Powell, Jonathan D. January 2005 (has links) (PDF)
Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, June 2005. / Thesis Advisor(s): Knox T. Millsaps. Includes bibliographical references (p. 73-74). Also available online.
24

Assessment of Raptor Migration Corridors in the United States

McHugh, Laura Jo, McHugh, Laura Jo January 2017 (has links)
Of the 36 diurnal raptor species in North America, 31 (~86%) are either complete or partial migrants. During fall and spring, raptors use "leading lines" or topographic features, such as mountain ranges, rivers, and coastlines that help guide them during their migration, and sometimes are redirected by diversion lines, or barriers that they are hesitant to cross (e.g., large bodies of water). Our objective was to assess the use of mountain ranges and rivers in central and southeastern Arizona by migrating raptors and to determine physical and ecological factors that are important to raptor migration across the United States. We counted migrating raptors in the spring and fall for two years at ten paired count stations in central and southeastern Arizona. Arizona counts were incorporated with counts from across the United States to determine physical and ecological features that influence migration rates. Raptor counts for central and southeastern Arizona averaged 2.0 raptors/hour, and were similar to what is observed at most other counting stations in the Central and Pacific Flyways. Stepwise regression models for the United States indicated counts were negatively related to distance from a diversion barrier and positively related to continuity of elevation. Understanding the factors that influence migrating raptors will inform decisions about environmental modifications and their potential influence on raptor populations. The following appendices are written and formatted to be submitted to journals. Although part of a thesis, they are written in plural to reflect the necessary authorship for journal submission. The first appendix, titled "Assessment of raptor migration corridors in central and southeastern Arizona", will be submitted to the Southwestern Naturalist. The second appendix, title "Assessment of raptor migration corridors in the United States", will be submitted to the Journal of Raptor Research.
25

Využití nástrojů projektového managementu při řízení IT projektů / The Use of Metohods of the Project Management in IT Projects

Svobodová, Sára January 2019 (has links)
In diploma thesis I deal with project proposal for selected company using theoretical knowledge, methods and tools of project management. The first part describes the basic terms of the project and project management, and then the project phases. In the second part of the thesis I deal with the analysis of the company and continue with the proposal of the project of the implementation of the active access node in a particular place of the network.
26

Experimental Study of Effects of Leading-Edge Structures on the Dynamic Stall of a Vertical Axis Wind Turbine Airfoil

Zhao, Jiaming January 2020 (has links)
Vertical axis wind turbine, developed as one of the main methods to utilize the wind energy, has a promising future; however, the major issue to limit its performance is the uneven loading on the blade during operation. Flow control mechanisms have been employed in the aerodynamic field to improve the performance of airfoils. In this study, two types of leading-edge structures, including flexible leading-edge and leading-edge roughness, are experimentally investigated to analyze their effects on altering the aerodynamic characteristics of NACA 0018 airfoil under steady flow condition and dynamic pitching condition. Current experimental results indicate that 1) during the steady flow condition, both of leading-edge structures contribute to the delay of the static stall; 2) for the dynamic pitching process, the leading-edge structures either delayed the dynamic stall angle or increased the area of the coefficient of pressure loop as a function of angle of attack.
27

Motivic Stratification in Fauré's Late Chamber Works: Perspectives on Voice Leading and Tonal Coherence

Bilik, Matthew Allan 08 1900 (has links)
This dissertation argues how motivic saturation on the musical surface complicates a conventional harmonic interpretation in Fauré's late chamber works. Using motivic segmentation and linear analysis, I illustrate how the abundance of foreground motives has far-reaching implications for tonal voice leading and overall coherence. The outcomes of motivic saliency are twofold, influencing harmonic progressions by 1) altering traditional syntax or 2) replacing traditional syntax to provide the primary form of tonal coherence. I unpack the voice-leading consequences of stratifying motives over one another and bring in two larger, emerging concepts: 1) key duality as disjunction between melody and bass and 2) tonal coherence from the tonal profile of motives. In the first case, either the melody or the bass projects its own center or key separate from the other parts, producing a sensation of key duality. In the second, a single motive furnishes the main source of tonal grounding by unfolding a structural harmony that the surface sonorities obscure. While motivic saliency is a consistent trait across Fauré's late repertoire, the two phenomena above increase over time.
28

Soul-Leading in Plato's Phaedrus and the Iconic Character of Being:

Brown, Ryan M. January 2021 (has links)
Thesis advisor: Marina McCoy / Since antiquity, scholars have observed a structural tension within Plato’s Phaedrus. Thedialogue demands order in every linguistic composition, yet it presents itself as a disordered composition. Accordingly, one of the key problems of the Phaedrus is determining which—if any—aspect of the dialogue can supply a unifying thread for the dialogue’s major themes (love, rhetoric, writing, myth, philosophy, etc.). My dissertation argues that “soul-leading” (psuchagōgia)—a rare and ambiguous term used to define the innate power of words—resolves the dialogue’s structural tension. I clarify the conceptual and dramatic features of soul-leading by focusing on the dialogue’s uniquely prevalent use of the semantic network of “leading” and “following.” By continuing to foreground the language and drama of leading and following, I offer a new interpretation of the dialogue as a whole: the Phaedrus is Plato’s articulation of how the soul can be led into communion with reality. Chapter 1 discusses scholarly disputes about the unity of the Phaedrus and proposes that soulleading adequately satisfies the criteria put forward for what would count as a unifying element. I argue that soul-leading unifies the dialogue both thematically and non-thematically; moreover, soul-leading is a theme capacious enough to account for the other principal contenders for unity put forward. Chapter 2 develops the ambiguous character of soul-leading by examining how the dialogue showcases dangerous forms thereof. Love and language are dangerous when they lead the soul toward goods which can never truly fulfill it. In order to clarify how love and language can mislead the soul, Socrates develops a set of accounts of how the soul is led, both internally and externally, in the three speeches on love. If the soul is to be led into communion with reality (the proper end of soul-leading), it must be led internally by the right part of the soul and externally by the right object of desire. Chapter 3 argues that all souls can, in principle, be harmonized and directed in the way that Chapter 2 requires. I show that Plato’s view of philosophy is neither elitist (i.e., some are intrinsically incapable of philosophy) nor naively essentialist. All can come into communion with reality because all are by nature equipped to do so. While Plato recognizes that there are forces which tend to prohibit one from exercising one’s capability of being rightly led, none of them are intrinsic to human nature. Chapter 4 argues that successful soul-leading require neither the leader nor the follower to be already well-disposed to what’s ultimate in order for the pair to come to a communion with what’s ultimate. Plato’s depiction of soul-leading love shows that love can itself promote the formation needed for both leader and follower to come into contact with reality. Love can do so because it is always already bound up reality in its responsiveness to beauty. Beauty itself calls the lover to itself by shining through the beautiful beloved, who acts as a reminder of transcendent Beauty. The lover mediates this same experience for the beloved. Each comes to desire the other as well as Beauty itself. Chapter 5 argues that the drama of the lovers’ formation mythically depicted in the Palinode (Chapter 4) is written into the drama of the dialogue as a whole. In the relationship between Socrates and Phaedrus, we see an enactment of love’s formative role. Likewise, in the relationship between Phaedrus and Lysias, we see an enactment of the dangerous soul-leading discussed in Chapter 2. My focus on leading and following also allows me to show the thematic significance of the drama’s setting. Chapter 6 articulates the metaphysical conditions under which one can be led into communion with reality. Transcendent Beauty invites us into communion with itself and makes possible our ascent by providing us with divine guides and images which can transport us from our ordinary experiences to the true beings. Beauty accomplishes its work—leading us in a “divine dance” where we follow the gods up to Beauty and back down to each other—through images. When we handle images of reality rightly, they lead our souls into communion with reality. Further, when we have come into communion, we’ll be inspired to be co-workers of Beauty’s soul-leading work. When we articulate reality in language, we create new images that can serve to lead others toward reality. / Thesis (PhD) — Boston College, 2021. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Philosophy.
29

Measurements and modeling of turbulent consumption speeds of syngas fuel blends

Venkateswaran, Prabhakar 19 February 2013 (has links)
Increasingly stringent emission requirements and dwindling petroleum reserves have generated interest in expanding the role of synthesis gas (syngas) fuels in power generation applications. Syngas fuels are the product of gasifying organic-based feedstock such as coal and biomass and are composed of mainly H₂ and CO. However, the use of syngas fuels in lean premixed gas turbine systems has been limited in part because the behavior of turbulent flames in these mixtures at practical gas turbine operating conditions are not well understood. This thesis presents an investigation of the influence of fuel composition and pressure on the turbulent consumption speed, ST,GC, and the turbulent flame brush thickness, FBT, for these mixtures. ST,GC and FBT are global parameters which represent the average rate of conversion of reactants to products and the average heat release distribution of the turbulent flame respectively. A comprehensive database of turbulent consumption speed measurements obtained at pressures up to 20 atm and H₂/CO ratios of 30/70 to 90/10 by volume is presented. There are two key findings from this database. First, mixtures of different H₂/CO ratios but with the same un-stretched laminar flame speeds, SL,0, exposed to the same turbulence intensities, u'rms , have different turbulent consumption speeds. Second, higher pressures augment the turbulent consumption speed when SL,0 is held constant across pressures and H₂/CO ratios. These observations are attributed to the mixture stretch sensitivities, which are incorporated into a physics-based model for the turbulent consumption speed using quasi-steady leading points concepts. The derived scaling law closely resembles Damkhler's classical turbulent flame speed scaling, except that the maximum stretched laminar flame speed, SL,max, arises as the normalizing parameter. Scaling the ST,GC data by SL,max shows good collapse of the data at fixed pressures, but systematic differences between data taken at different pressures are observed. These differences are attributed to non-quasi-steady chemistry effects, which are quantified with a Damkhler number defined as the ratio of the chemical time scale associated with SL,max and a fluid mechanic time scale. The observed scatter in the normalized turbulent consumption speed data correlates very well with this Damkhler number, suggesting that ST,GC can be parameterized by u'rms/SL,max and the leading point Damkhler number. Finally, a systematic investigation of the influence of pressure and fuel composition on the flame brush thickness is presented. The flame brush thickness is shown to be independent of the H₂/CO ratio if SL,0 is held constant across the mixtures. However, increasing the equivalence ratio for lean mixtures at a constant H₂/CO ratio, results in a thicker flame brush. Increasing the pressure is shown to augment the flame brush thickness, a result which has not been previously reported in the literature. Classical correlations based on turbulent diffusion concepts collapse the flame brush thickness data obtained at fixed u'rms/U₀ and pressure reasonably well, but systematic differences exist between the data at different u'rms/U₀ and pressures.
30

Leading smoothly: hidden dimensions of leadership

Ulusoy, Cisil, Alev, Ajda January 2011 (has links)
This research aims to understand, describe and analyze the hidden dimensions of leadership that can nourish leader-follower relationships. Additionally, by analyzing empirical illustrations combined with the theories presented in the literature, we have developed a framework for leading smoothly, which can provide insights into the leadership activities that leaders and executives can benefit from. Our findings on leading smoothly emerged during our analysis and interpretation of two case studies and our literature review, and led us to concentrate on emotional and communicational dimensions of leadership. Concerning crisis and turbulent times as one of the most challenging situations for performing leadership activities, we present two case studies related to leadership approaches during crises. One of the case studies is about the leadership of BP‟s former CEO Tony Hayward during the oil spill crisis in the Gulf of Mexico in 2010, and the second case is about the leadership of the former CEO of Johnson & Johnson during the Tylenol crisis in 1982. While analyzing the cases, the emotional and communicational approaches of leaders are examined. Furthermore, these case studies facilitate the identification of the aspects that smooth leadership activities and their impacts on the leader follower relationships. Consequently, the study discusses the emotional and communicational dimensions of leadership and presents the framework for leading smoothly as a different perspective for embellishing the interaction between the leader and the follower, which can provide an understanding of the subtle ways of leading.

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