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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.
301

Time and architectural representations: the illusion of being eternal

Simon Grell, Sofi January 2014 (has links)
Att beskriva en byggnad som tidlös är bland det finaste en kan säga. Några av världens mest uppskattade byggnader har beskriv- its som just det, tidlösa. Hur kommer det sig att en av den finaste komplimangen och erkännandet en byggnad kan få, egentligen är intetsägande?Tiden går ständigt och det finns ingenting någon kan göra för att ändra det. Människor, djur och även byggnader utvecklas och åldras. I denna uppsats ska jag undersöka hur det kommer sig att arkitekter tenderar att undvika att tiden påverkar arkitektur, både i hur den skapas och i hur den representeras. / One of the greatest compliments a building can receive, is to be described as timeless. Some of the most appreciated buildings in the world has been described just as that, timeless or eternal. How is that, that one of the best compliments and acknowledgementsa building can receive, dosen’t really say anything about the build- ing?Time goes by and there is nothing anyone can do about it. People, animals and even building get old. In this essay, I will ex- amine why architects tends to avoid that time gets to architecture, both by how it is created and in the architectural representations.
302

Blicking through video chats: The role of contingency in toddlers' ability to learn novel verbs

Roseberry, Sarah January 2011 (has links)
Language learning takes place in the context of social relationships. Yet, we know little about the mechanisms that link social interaction to word learning. This dissertation focuses on two aspects of that relationship, social contingency and eye gaze, and asks whether these cues may be a critical ingredient in the well established link between social support and language learning. Specifically, we investigate how toddlers learn novel verbs in one of three conditions. In one, training on four new words was conducted using live interaction. In the second, children were trained on the same words using a contingent screen condition (video-chat). Finally, in the third, they were taught the same words in a video condition that did not maintain social contingency (yoked video). Results suggest that children exposed to novel verbs via contingent screen condition learned these words to the same degree as children in the live condition and far exceeded their peers who were exposed to non-contingent video only. Analysis of looking patterns during training further suggests that children in contingent interactions rely on eye gaze during social interactions, which predicts language learning. Taken together, this dissertation begins to operationally define social cues and to illuminate the mechanism that links social interaction and language acquisition. It also speaks to the literature on learning through screen media as the first study to examine word learning through video chat technology. / Psychology
303

Actions speak louder than words: The role of adaptive contingency in language development

Reed, Jessica Michele January 2015 (has links)
Sensitive and responsive parenting promotes adaptive outcomes for children. Within the domain of language development, responsiveness has been examined through the effects of temporal and semantic contingency on children’s vocabularies. The term adaptive contingency can be used to characterize the process whereby dyads co-construct common ground, establishing a co-dependence of both timing and meaningfulness. This dissertation examined the role of adaptive contingency in early verb learning by examining the learning consequences when timing is manipulated but meaning is held constant (Study 1) and when meaningfulness is manipulated but timing is held constant (Study 2). In a previous study, toddlers learned novel action words when teaching was uninterrupted, but failed to do so when caregivers were interrupted while teaching by a cell phone call from the experimenter (Reed, Hirsh-Pasek, & Golinkoff, in preparation). Study 1 explored how the timing of interruptions differentially affects word learning. Experimenters blind to study hypotheses taught two-year old toddlers novel words, and learning was assessed via the Intermodal Preferential Looking Paradigm (IPLP). During the teaching period, experimenters responded to text messages, momentarily disrupting the teaching. The timing of these interruptions occurred (1) in the middle of an utterance, such that the label and demonstration of its action referent were decoupled, (2) before the “label + action referent” event occurred, or (3) after (the control condition). At test, only children in the after condition learned the novel words. Study 2 examined whether word learning would be disrupted when teaching interactions were interrupted by an event that breaks the shared focus (e.g., a cell phone call) but not when the interruption shifts the shared context (e.g., when a lighted display suddenly shines). Novel words were learned in one of three experimental conditions (light display to shift attention, cell phone call to break attention, no interruption control), and learning was again assessed via the IPLP. Only toddlers in the shift condition learned the novel words. This dissertation contributes to the growing recognition that the quality of interactions with caregivers affects children’s language trajectories (e.g., rich and diverse vocabulary, Rowe, 2012; fluent and connected bouts of sustained joint attention, Hirsh-Pasek et al., in press). Utilizing ecologically valid interruptions, the two studies together illuminate how the social context can support or hinder early verb learning. / Psychology
304

Therapy development of group contingency management in methadone treatment: Pilot 1 - the application of a percentile schedule to enhance attendance behaviors and cocaine abstinence

Rosenwasser, Beth January 2008 (has links)
In an effort to adapt a prize-based attendance and abstinence reinforcement program to the group therapy modality typically found in community substance abuse treatment, this study applied a contingency management (CM) procedure to behavior outcomes of the group as a whole. An algorithmic shaping percentile schedule was used to establish the outcome criteria determining group access to prize bowl drawings. Both the shaping schedule and hypothesized positive social support secondary to interdependent group contingencies aimed to initiate cocaine abstinence among cocaine abusing methadone-maintained participants having initial low rates of cocaine abstinence. In a multiple baseline across behaviors with reversals design, the procedure was applied to four target behaviors in sequence: incentive group attendance, urinalysis appointment attendance, opiate and cocaine abstinence. Results demonstrated clear improvement in group attendance during the shaping schedules. Effects on opiate abstinence were promising but not definitive; an increase in magnitude of reinforcement yielded a better response. There were no effects on cocaine abstinence using the percentile schedules tried. When shaping was conducted by an experienced psychologist in conjunction with an average 4-fold increase in reinforcer magnitude, 55% achieved some abstinence (compared to 18% in baseline). Participants were monitored for safety due to concern about coercion; no instances of physical violence occurred and infrequent instances of verbal negativity were managed using typical outpatient procedures. Results indicate that interdependent group CM is efficacious for attendance, and a feasible and acceptable procedure with appropriate monitoring. Future studies are needed to determine effective and appropriate shaping and reinforcement schedules in group CM to increase drug abstinence. / Educational Psychology
305

Managing the Risk of Failure in Complex Systems: Insight into the Space Shuttle Challenger Failure

Vantine, William L. 17 December 1998 (has links)
This dissertation presents a new approach for identifying, assessing, mitigating, and managing the risks of failure in complex systems. It describes the paradigm commonly used today to explain such failures and proposes an alternative paradigm that expands the lens for viewing failures to include alternative theories derived from modern theories of physics. Further, it describes the foundation for each paradigm and illustrates how the paradigms may be applied to a particular system failure. Today, system failure commonly is analyzed using a paradigm grounded in classical or Newtonian physics. This branch of science embraces the principles of reductionism, cause and effect, and determinism. Reductionism is used to dissect the system failure into its fundamental elements. The principle of cause and effect links the actions that led to the failure to the consequences that result. Analysts use determinism to establish the linear link from one event to another to form the chain that reveals the path from cause to consequence. As a result, each failure has a single cause and a single consequence. An alternative paradigm, labeled contemporary, incorporates the Newtonian foundation of the classical paradigm, but it does not accept the principles as inviolate. Instead, this contemporary paradigm adopts the principles found in the theories of relativity, quantum mechanics, chaos, and complexity. These theories hold that any analysis of the failure is affected by the frame of reference of the observer. Causes may create non-linear effects and these effects may not be observable directly. In this paradigm, there are assumed to be multiple causes for any system failure. Each cause contributes to the failure to a degree that may not be measurable using techniques of classical physics. The failure itself generates multiple consequences that may be remote in place or time from the site of the failure, and which may affect multiple individuals and organizations. Further, these consequences, are not inevitable, but may be altered by actions taken prior to and responses taken after the occurrence of the failure. The classical and contemporary paradigms are applied using a single embedded case study, the failure of the space shuttle Challenger. Sources, including literature and popular press articles published prior to and after the failure and NASA documents are reviewed to determine the utility of each paradigm. These reviews are supplemented by interviews with individuals involved in the failure and the official investigations that followed. This dissertation demonstrates that a combination of the classical and contemporary paradigms provides a more complete, and more accurate, picture of system failure. This combination links the non-deterministic elements of system failure analysis to the more conventional, deterministic theories. This new framework recognizes that the complete prevention of failure cannot be achieved; instead it makes provisions for preparing for and responding to system failure. / Ph. D.
306

Studies on Data-Driven Discourse Relation Recognition toward Natural Language Understanding / 自然言語理解に向けたデータ駆動の談話関係認識に関する研究

Ohmura, Kazumasa 25 March 2024 (has links)
付記する学位プログラム名: デザイン学大学院連携プログラム / 京都大学 / 新制・課程博士 / 博士(情報学) / 甲第25418号 / 情博第856号 / 新制||情||143(附属図書館) / 京都大学大学院情報学研究科知能情報学専攻 / (主査)特定教授 黒橋 禎夫, 教授 河原 達也, 教授 楠見 孝 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM
307

Improved Dynamical Analysis Tools for DFIG Wind Farms via Traditional and Koopman Linearizations

Mitchell-Colgan, Elliott 27 September 2019 (has links)
The electric power system is designed to economically and reliably transmit electricity to homes, industry, and businesses. The economic impact of the electric grid was demonstrated by the 2003 blackout's visible impact in the graph of the yearly gross domestic product of the Unites States. However, because the number of customers is so large and economies of scale are leveraged to keep electricity prices low, utilities are strongly interconnected. Performing comprehensive engineering analyses to ensure reliable operation is still impossible. Instead, heuristics and safety factors are incorporated into planning processes to continually meet demand in a way that complies with Federal regulations. As evidenced by the infrequency of blackouts in the United States, the sophisticated planning processes have up to date been relatively successful. However, the power system is constantly changing. Electrical generators based on renewable energies are a beneficial addition to the grid, but these and other technological changes like high-voltage power electronic converters also come with their own challenges. These systems as currently employed tend to have a different impact on the reliability of operation than traditional fossil fuel based generators. As the system changes, so do the engineering analyses required to ensure reliable operation. In particular, the wind energy conversion systems (WECS) negatively impact the response of the grid to disturbances in certain ways due to inherent challenges harnessing the wind as an energy sources. These negative impacts (and the advent of powerful personal computing) require an increase in the sophistication of power system models. Thus, there are competing challenges: the scale of the power system necessitates computationally efficient modeling, but the complexity of analysis required to maintain reliable operation is also increasing. The primary aim of this study is to develop models and methods for more detailed yet computationally manageable simulation. To this aim, higher order linearizations and the properties of linear systems (graph theory and linear algebra) are exploited. More specifically, this document contains three studies. In the short term planning and situational awareness context, a method is proposed to quickly check credible outages of important grid equipment. This methodology enables the inspection of a wider breadth of system conditions to ameliorate the negative impacts of the unpredictability of the wind. A linear model in the traditional sense is also developed to model any arbitrary number of wind turbines in a wind farm. This enables industry players to study the impacts wind turbine interaction on the dynamic stability of the grid in response to small disturbances. Finally, a wind farm is modeled as a large matrix to model even nonlinear behavior of wind farms. This helps industry players analyze the impact of large disturbances on the grid. / Doctor of Philosophy / The electric power system is designed to economically and reliably transmit electricity to homes, industry, and businesses. The economic impact of the electric grid was demonstrated by the 2003 blackout’s visible impact in the graph of the yearly gross domestic product of the United States. However, because the number of customers is so large and economies of scale are leveraged to keep electricity prices low, utilities are strongly interconnected. Performing comprehensive engineering analyses to ensure reliable operation is still impossible. Instead, heuristics and safety factors are incorporated into planning processes to continually meet demand in a way that complies with Federal regulations. As evidenced by the infrequency of blackouts in the United States, the sophisticated planning processes have up to date been relatively successful. However, the power system is constantly changing. Electrical generators based on renewable energies are a beneficial addition to the grid, but these and other technological changes like high-voltage power electronic converters also come with their own challenges. These systems as currently employed tend to have a different impact on the reliability of operation than traditional fossil fuel based generators. As the system changes, so do the engineering analyses required to ensure reliable operation. In particular, the wind energy conversion systems (WECS) negatively impact the response of the grid to disturbances in certain ways due to inherent challenges harnessing the wind as an energy sources. These negative impacts (and the advent of powerful personal computing) require an increase in the sophistication of power system models. Thus, there are competing challenges: the scale of the power system necessitates computationally efficient modeling, but the complexity of analysis required to maintain reliable operation is also increasing. The primary aim of this study is to develop models and methods for more detailed yet computationally manageable simulation. To this aim, higher order linearizations and the properties of linear systems (graph theory and linear algebra) are exploited. More specifically, this document contains three studies. In the short term planning and situational awareness context, a method is proposed to quickly check credible outages of important grid equipment. This methodology enables the inspection of a wider breadth of system conditions to ameliorate the negative impacts of the unpredictability of the wind. A linear model in the traditional sense is also developed to model any arbitrary number of wind turbines in a wind farm. This enables industry players to study the impacts wind turbine interaction on the dynamic stability of the grid in response to small disturbances. Finally, a wind farm is modeled as a large matrix to model even nonlinear behavior of wind farms. This helps industry players analyze the impact of large disturbances on the grid.
308

A Line Outage Study for Prediction of Static Power Flow Redistribution

Wei, Nan 06 September 2016 (has links)
Transmission line is a crucial role in power transmission network which connects generating units to consumers. Some unpredicted failure events such as lightening or system faults can cause transmission line tripped, which may bring about a large interruption to the system and causes damage. When line outage happens, the power flow on the tripped line will be redistributed to the rest of lines in the system. It may cause risk of overload happens on other lines, and results in a cascading failure and system collapse. Reasonably, a single line outage will not affect all other lines in the system. Therefore, when a line outage happens, it is important for the system operator to have a preview of which lines will have serious impact and which lines will not, so that the operator can only focus on monitoring certain lines which will be seriously affected, rather than keeping monitoring the whole system. In this thesis, A Line Outage Distribution Factor (LODF) method is proposed and implemented in the IEEE 118 bus system to estimate active power flow redistribution after a line outage. After that, a definition of Thevenin electrical distance between two transmission lines is derived and applied to calculate electrical distances between the outage line and each line in the system. An exponential convergence tendency is found between maximum possible LODF predicted power flow variations and electrical distance, and an exponential regression method is applied to analyze this tendency. The contribution of this work is a rule has been found that starting from the outage line, the maximum possible active power flow variation on transmission lines exponentially decreases exponentially while the electrical distance increases. With only the information of system's normal operating condition and topological information, the maximum possible active power change on each lines caused by single line outage, and the margin of the impact of single line outage on power flow variations may propagate along electrical distance can be easily and quickly predicted. Ultimately, the goal of this work is to allow operators at the control center can concentrate on lines within a certain electrical distance instead of keeping monitoring the whole system when a line outage happens. / Master of Science
309

Navigating Crisis : A Quantitative Study on Corporations’ Strategic Decisions Regarding the Russia-Ukraine War.

Deumic, Mirza, Palmqvist, Max January 2024 (has links)
Background: In 2022, Russia invaded Ukraine and put the world into a state of geopolitical crisis, leading to severe negative spillover effects on the global economy. Corporations were compelled to respond to the geopolitical crisis, while some were indirectly exposed to the war and others directly affected, all corporations had to decide on their strategic actions. Thus, questions arise how and why corporations acted as they did. Purpose: The purpose of this study is to explore how corporations react to a geopolitical crisis, and further explain how they make their strategic decisions. The study adopts a contingency perspective to identify the fundamental basis upon which strategic decisions were made. Additionally, the study tests whether stakeholders’ influences can explain the corporations’ decisions. Method: This study employs a quantitative methodology with a deductive approach in an exploratory and positivistic paradigm. This is done to examine the relationship between corporations’ exposure to Russia, stakeholders’ influences, and strategic decisions regarding the Russia-Ukraine war. Data were gathered from annual reports and various databases, and analyzed using Spearman correlation matrix and linear regression models. Conclusion: The findings show that corporations act differently depending on their contingencies in reaction to a geopolitical crisis. Furthermore, stakeholders influence the strategic decisions in corporations indirectly affected by the geopolitical crisis, however, their influence is diminished in corporations directly impacted. While some stakeholder influences were found on the strategic decisions made by the most severely impacted corporations, other factors seem to ultimately determine the strategic decisions in the directly impacted corporations.
310

Guardians of Financial Integrity : A quantitative study investigating Contingencies in Board Independence and EarningsManagement

Hajder, Dino, Steen, Joel January 2024 (has links)
Background: Earnings management has been a popular topic of discussion for many decades, and researchers always look for underlying factors that can reduce the phenomenon. A common subject for this has been board independence, and the implications that independent directors have on earnings management. Additionally, researchers have argued that legal protection is a big part in how independent directors can exercise their monitoring, as well as the use of control-enhancing mechanisms (CEM). Purpose: To investigate the relationship between board independence and earnings management. This thesis will also examine if shareholder protection and CEMs respectively affect independent directors´ ability to reduce earnings management. Method: This thesis adopts a positivistic view with a deductive approach using a quantitative method where data was collected using databases, websites, and annual reports. Further, the data was analyzed using a Spearman correlation matrix and an OLS regression for each hypothesis. Findings: The findings show that there exists no relationship between board independence and earnings management. Furthermore, the thesis does not find support that shareholder protection has a moderating influence on the relationship, and thus has no effect on independent directors’ability to reduce earnings management. However, the thesis finds indications that firms who have the CEM of dual-class shares experience increase in earnings management as the share of independent directors increases.

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