• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1806
  • 431
  • 175
  • 166
  • 104
  • 27
  • 25
  • 19
  • 19
  • 13
  • 11
  • 9
  • 9
  • 9
  • 7
  • Tagged with
  • 3472
  • 707
  • 510
  • 354
  • 349
  • 330
  • 320
  • 316
  • 307
  • 287
  • 267
  • 233
  • 232
  • 217
  • 214
  • 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

Grandparent Support for Families with Non-Biological Adopted Children

Sayre, Jennifer Ann 03 June 2014 (has links)
Adoption is an important family structure in The United States. In 2013, more than 1.7 million children were adopted including domestic, International, and foster care adoptions in the U.S. I examine the perceived and received support from grandparents to adoptive families and the impact it has on the families' lives. Qualitative methods in the form of semi-structured open-ended interviews were used to conduct 28 interviews with adoptive parents. My findings reveal that maternal grandmothers were more likely to be supportive and involved in adoptive families compared to other grandparents. Secondly, perceived support was directly mentioned or implied by every adoptive family. Third, single mothers expressed more desire for and instances of grandparent support. Fourth, the majority of grandparents who were initially hesitant or reluctant about adoption were later supportive and accepting of the adopted child(ren). Fifth, most adoptive families received and perceived support. However, some families who did not receive or perceive much support were able to find alternative support systems. Finally, verbal and emotional supports were the most reported forms of support from grandparents to adoptive families. Almost all adoptive families reported some level of emotional and/or verbal support from one or more grandparent. Future research can more thoroughly examine family outcomes from grandparent support. Looking at the other support systems adoptive families use is an additional area of future research. / Ph. D.
322

Utility Asset Management Programming: Performance, Sustainability and Resilience - Moving from Academia to Practice

Pedicini, Sarah Elizabeth 20 March 2014 (has links)
Many utility asset management programs have been developed following the U.S. Environmental Protection Agency (EPA) core definition of maintaining a level of service at the lowest life cycle cost. Most utilities, however, only incorporate performance measures into their asset management plans. A holistic approach to asset management is more beneficial because it takes into account the short and long term goals of the utility and can provide better service socially, economically, and environmentally. An analysis of the Town of Blacksburg wastewater utility's practices and data collection was performed using a holistic asset management framework developed at Virginia Tech. This theoretical framework supports the three key aspects of asset management: performance, sustainability, and resilience. Where gaps were identified, recommendations were made as to what practices, goals, and data the Town can add to their current plan so that their program is more holistic. Research has shown that many utilities have trouble adapting to asset management plans because job roles and responsibilities change and are often not well defined. To help the Town of Blacksburg adapt to their new asset management plan with performance, sustainability and resiliency goals, a work process flow was designed. A work process flow allows for visible changes in job responsibility to be more easily recognized as well as allow for future changes to be made. / Master of Science
323

An Integrated Real-Time and Security Scheduling Framework for CPS

Kansal, Kriti 18 May 2023 (has links)
In the world of real-time systems (RTS), security has often been overlooked in the design process. However, with the emergence of the Internet of Things and Cyber-Physical Systems, RTS are now frequently used in interconnected applications where data is shared regularly. Unfortunately, this increased connectivity has also led to a larger attack surface. As a result, it is crucial to redesign RTS to not only meet real-time requirements but also to be resilient to threats. To address this issue, we propose a new real-time security co-design task model, and an accompanying scheduling framework, where schedulability can be used to indicate whether both real-time and security requirements are met. Our algorithm is designed to be flexible, allowing different security mechanisms to be used along with real-time tasks. Specifically, we augment the frame-based task model by introducing an n-dimensional security matrix, which serves as a powerful tool to enable our approach. This matrix clearly indicates which defense mechanisms are available for each task in the system by storing the worst-case execution times of tasks. Then, we transform the problem of maximizing security, subject to schedulability, into a variant of the knapsack problem. To make this approach more practical, we implement a fully polynomial time approximation scheme (FPTAS) that reduces the time complexity of solving the knapsack problem from a pseudo-polynomial to a fully polynomial. We also experiment with a greedy-heuristic approach and compare the results of both algorithms. / Master of Science / Real-time systems are computer systems that need to respond to events in a timely manner. In the past, these systems were designed without much consideration for security. However, with the increasing use of interconnected devices and systems, it has become important to make sure that real-time systems are secure and protected against malicious attacks. To address this issue, we propose a new approach for designing real-time systems that prioritizes security from the very beginning. Our approach allows for different security tasks to be executed depending on the system's needs, and we use a two-dimensional security matrix to help with this. We also introduce a way to solve the security problem that is faster and more efficient than previous methods. Our experimental results show that our new approach significantly reduces the time and effort required to solve the security problem while still producing good results.
324

The Flow Regime of Function: Influence of flow changes on biogeochemical processes in streams

O'Donnell, Brynn Marie 02 July 2019 (has links)
Streams are ecosystems organized by disturbance. One of the most frequent disturbances within a stream is elevated flow. Elevated flow can both stimulate ecosystem processes and impede them. Consequently, flow plays a critical role in shifting the dominant stream function between biological transformation and physical transportation of materials. To garner further insight into the complex interactions of stream function and flow, I assessed the influence of elevated flow and flow disturbances on stream metabolism. To do so, I analyzed five years of dissolved oxygen data from an urban- and agriculturallyinfluenced stream to estimate metabolism. Stream metabolism is estimated from the production (gross primary production; GPP) and consumption (ecosystem respiration; ER) of dissolved oxygen. With these data, I evaluated how low and elevated flows differentially impact water quality (e.g., turbidity, conductivity) and metabolism using segmented metabolism- and concentration- discharge analyses. I found that GPP declined at varying rates across discharge, and ER decreased at lower flows but became constant at higher flows. Net ecosystem production (NEP; = GPP - ER) reflected the divergence of GPP and ER and was unchanging at lower flows, but declined at higher discharge. These C-Q patterns can consequently influence or be influenced by changes in metabolism. I coupled metabolism-Q and C-Q trends to examine linked flow-induced changes to physicochemical parameters and metabolism. Parameters related to metabolism (e.g., turbidity and GPP, pH and NEP) frequently followed coupled trends. To investigate metabolic recovery dynamics (i.e., resistance and resilience) following flow disturbances, I analyzed metabolic responses to 15 isolated flow events and identified the antecedent conditions or disturbance characteristics that most contributed to recovery dynamics. ER was both more resistant and resilient than GPP. GPP took longer to recover (1 to >9 days, mean = 2.5) than ER (1 to 2 days, mean = 1.1). ER resistance was strongly correlated with the intensity of the flow event, whereas GPP was not, suggesting that GPP responds similarly to flow disturbances, regardless of the magnitude of flow event. Flow may be the most frequent disturbance experienced by streams. However, streams are exposed to a multitude of other disturbances; here I also highlight how anthropogenic alterations to streams – namely, burying a stream underground – can change biogeochemical function. This thesis proposes novel frameworks to explore the nexus of flow, anthropogenic disturbances, and stream function, and thereby to further our understanding of the complex relationship between streams and disturbances. / Master of Science / A stream is defined by its flowing water. Flow brings the nutrients, organic matter, and other materials necessary to the algae and bacteria within the stream as well as the invertebrates and fishes they sustain, and is consequently integral to in-stream biology and ecology. However, elevated flow is also one of the most frequent disturbances experienced by streams. Elevated flow dilutes or enriches concentrations of water quality parameters, moves the water faster, reduces the amount of time essential nutrients are available to organisms within streams, and scours the algae and bacteria on stream bottoms. Here, I analyzed five years of data from an urban- and agriculturally-influenced stream and estimated stream metabolism to explore the influence of flow on stream biology, chemistry, and ecology. Stream metabolism is a process that reflects the respiration and photosynthesis of bacteria and algae, estimated from the production and consumption of dissolved oxygen. The primary research objective of my thesis was to investigate how changing flow impacts metabolism, by: (1) examining how low and high flows impact metabolism differently, and (2) studying the response and recovery of metabolism following multiple flow disturbances. Flow not only influences in-stream biology and processes, such as stream metabolism, but also changes the water quality of the stream (e.g., conductivity, pH, turbidity). To examine the interconnection between flow-induced changes to water quality parameters and metabolism, I measured how low and high flows impacted water quality and then compared water quality-flow relationships with metabolism at low and high flows. I found that metabolic processes and related water quality parameters were frequently coupled. Next, to test how water quality might also influence the response and recovery of metabolism after a flow disturbance, I examined whether prior environmental conditions (e.g., temperature, light) or the magnitude of the flow disturbance influenced metabolic response and recovery. I found that the size of the flow disturbance did change a critical piece of stream metabolism. Flow is not the only prevalent disturbance streams face: increasingly, streams are being altered by ongoing urban and suburbanization. Therefore, to highlight the full suite of disturbances to streams caused by human modification, I wrote a public science communication piece documenting the biological, chemical, and ecological ramifications of burying streams underground. Ultimately, this thesis proposes new frameworks to more adequately explore the complex relationships between water quality, stream ecology, and disturbances.
325

Boundary Resilience: A New Approach to Analyzing Behavior in Complex Systems

Wilhelm, Julia Claire Wolf 30 April 2024 (has links)
Systems engineering has many subdisciplines which would be useful to study in terms of complex system behavior. However, it is the interactions between a complex system and its operating environment which drive the motivation for this analysis. Specifically, this work introduces a new approach to assessing these interactions called "boundary resilience." While classical resilience theory measures a system's internal reaction to adverse event, boundary resilience evaluates the impacts such an event may have on the surrounding environment. As the scope of this analysis is quite large, it was deemed appropriate to conduct a case study to determine the fundamental tenants of boundary resilience. SpaceX's satellite Internet mega-constellation (StarLink) was chosen due to its large potential to impact the space environment as well as its size and complexity. This study produced two boundary resilience measures, one for local boundary resilience of a single component and one for the global boundary behavior of the entire system. The local metric measures the likelihood of an adverse event occurring at that boundary location as well as its potential to impact the surrounding environment. The global boundary resilience metric reflects a nonlinear relationship among the system components. / Doctor of Philosophy / It is no secret that the world and the systems which enable it to function have become increasingly complex in recent decades. This complexity has the potential to create both innovative uses as well as unplanned and unexpected behaviors in these systems. As they interact with their environment, complex systems can produce equally complex and unpredictable behaviors which have potential to have a negative impact on their environment. This work seeks to study one component of this behavior: resilience. Resilience usually measures a system's ability to continue providing a service in the event of a disruption, or to recover the ability to provide the service after some amount of time. Boundary resilience, on the other hand, takes the perspective of potential environmental damage caused by an adverse event, rather than damage to the system's functionality. This study uses a case study of the StarLink satellite constellation to examine this phenomenon. The outcome of the analysis shows that the size of a complex system negatively impacts its potential to cause damage to the surrounding environment, but increasingly mature components can mitigate this degradation.
326

Teacher Resilience in Central Virginia: How Veteran Teachers Become Resilient

Shields, Lee Brantley 14 April 2020 (has links)
The development of teacher resilience is important in improving teacher retention. This study identified reasons veteran teachers have remained in the classroom; individual and contextual factors of resilience; significant challenges the teachers have encountered; and strategies the teachers used for dealing with the challenging situations. This was a qualitative study that included interviews with 15 teachers in a rural school division in Central Virginia. Data analysis occurred through deductive coding of the transcribed interviews using qualitative data analysis software. The findings for this study identified seven factors that veteran teachers indicated were important in their decision to remain in the classroom. The study also identified 22 individual factors of resilience and 10 contextual factors presented through the experiences of the veteran teachers. The veteran teachers described four challenges that they have faced in their school division and the strategies they used to overcome those challenges. The study concludes with the discussion, implication, and conclusion of the findings. / Doctor of Education / The development of teacher resilience is important in improving teacher retention. This study identified reasons veteran teachers have remained in the classroom; individual and contextual factors of resilience; the most significant challenges the teachers have encountered; and strategies the teachers used for dealing with those challenging situations. This was a qualitative study that included interviews with 15 teachers in a rural school division in Central Virginia. The findings for this study provide practitioners with a framework to develop a resilient culture within their schools.
327

Gaps, traps, bridges and props: a mixed-methods study of resilience in the medicines management system for heart failure patients at hospital discharge

Fylan, Beth, Marques, Iuri, Ismail, Hanif, Breen, Liz, Gardner, Peter, Armitage, Gerry R., Blenkinsopp, Alison 2018 October 1924 (has links)
Yes / Poor medicines management places patients at risk, particularly during care transitions. For patients with heart failure (HF), optimal medicines management is crucial to control symptoms and prevent hospital readmission. This study explored the concept of resilience using HF as an example condition to understand how the system compensates for known and unknown weaknesses. We explored resilience using a mixed-methods approach in four healthcare economies in the north of England. Data from hospital site observations, healthcare staff and patient interviews, and documentary analysis were collected between June 2016 and March 2017. Data were synthesised and analysed using framework analysis. Interviews were conducted with 45 healthcare professionals, with 20 patients at three timepoints and 189 hours of observation were undertaken. We identified four primary inter-related themes concerning organisational resilience. These were named as gaps, traps, bridges and props. Gaps were discontinuities in processes that had the potential to result in poorly optimised medicines. Traps were features of the system that could produce errors or unintended adverse medication events. ‘Bridges’ were features of the medicines management system that promoted safety and continuity which ensured that, despite varying conditions, care could be delivered successfully. ‘Props’ were informal, temporary or impromptu actions taken by patients or healthcare staff to avoid potential adverse events. The numerous opportunities for HF patient safety to be compromised and sub-optimal medicines management during this common care transition are mitigated by system resilience. Cross-organisational bridges and temporary fixes or ‘props’ put in place by patients and carers, healthcare teams and organisations are critical for safe and optimal care to be delivered in the face of continued system pressures.
328

Building Spiritual Capital: The Effects of Kundalini Yoga on Adolescent Stress, Emotional Affect, and Resilience

Sarkissian, Meliné 18 March 2016 (has links) (PDF)
In order to integrate a mind, body, spirit approach in school settings, yoga programming such as Y.O.G.A. for Youth was introduced to one public and two charter schools in Los Angeles area urban neighborhoods. The study examined the effectiveness of the overall program and its effect on adolescent stress, emotional affect, and resilience. A survey was administered to measure the three dependent variables and informal interviews were conducted to determine the overall effectiveness of the program. The results of the mixed method approach indicated that the overall program was effective in creating a general sense of well-being and statistically significant in alleviating stress (p < .05), increasing positive affect (p < .05), and resilience (p < .001), in the participants (N=30).
329

Exploring the role of social capital mechanisms in cooperative resilience

Wulandhari, N.B.I., Gölgeci, I., Mishra, N., Sivarajah, Uthayasankar, Gupta, S. 13 March 2022 (has links)
Yes / We contribute to research on cooperative resilience by examining how their main advantage of social foundations may facilitate the assembly of resilience capabilities. Drawing from the social capital literature, we focus on the strategies and activities of a nationally known rural cooperative in Indonesia to reveal social capital mechanisms, specifically channeling and targeting social capital, that underlie diverse sets of resilience capabilities. By conceptualizing cooperative resilience according to cooperatives’ dual objectives of economic and social viability, we build an empirically grounded framework that encompasses social capital-driven mechanisms that underlie cooperative resilience. Economically, strengthening social capital (channeling) may result in organizational transparency and collaborative work, while widening social networks (targeting) develops velocity and flexibility. Socially, both mechanisms lead to the emergence of individual-level resilience capabilities. Our study informs business research on resilience by conceptualizing it in the context of cooperatives and shedding light on its underlying social capital-driven mechanisms.
330

High School Sport Participation: Effects on Students' Grit and Resilience

Waldman, Rory Kekoa-Israel 26 July 2024 (has links) (PDF)
Adolescence is a time of transition, growth, and identity exploration. Often this great time for growth is accompanied with an increase in stressors that can be detrimental to success and health, without the necessary coping mechanisms. It is a period of life where resilience and grit are extremely important. A post-traumatic growth definition for resilience allows for the possibility of a steeling effect, in which the resilience of an adolescent can grow and develop. Sport provides an ideal environment for the development of both grit and resilience by providing a safe environment for adversity to occur without detrimental consequences. In a previous study done by Caldarella et al. (2019), they explored sport and its effect on resilience in adolescents. However, this previous study only used a parent report. The current quasi-replication aimed to compare high school athletes and non-athletes and their levels of grit and resilience using an online self-report and parent report method with the Grit scale and SEARS measurement. I found that athletes who participate in three or more sports have higher levels of perceived resilience (p = .017). For future studies I recommend a larger sample size as well as examining how other extracurricular activities may impact grit and resilience.

Page generated in 0.4434 seconds