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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.
621

ESCALATION OF COMMITMENT AND THE EFFECTS OF THE PRESENCE OF AN ALTERNATIVE INVESTMENT, MAGNITUDE OF LOSS AND MONITORING: STOPPING A PROJECT WHICH IS 90% COMPLETE

Buxton, Mark Edward 01 January 2008 (has links)
Previous studies have shown the continuation of a failing project occurs in many aspects of business and government, and that the commitment to and continuation of a previous decision can even apply to waiting on a bus, attending a play and mountain climbing. The continuation of a failing project or decision has also been called escalation of commitment. Several theories have been suggested to explain the reasons managers continue failing or doubtful projects. Among those theories are Agency Theory, Self-Justification Theory, Prospect Theory, Approach Avoidance Theory, Self-Efficacy Theory and National Culture Theory. This study incorporates Agency Theory, Approach Avoidance Theory and Self-Justification Theory to explain the effects of an alternative investment, magnitude of loss and monitoring on the likelihood of continuing a project. The experimental design of the study was a 2 (presence of an alternative investment: yes or no) x 2 (monitoring: low or high) x 3 (magnitude of loss: low, medium or high) between-subjects factorial design. Likelihood of continuing a project was measured in two ways: first, dichotomously (either "yes" the subjects continued the project, or "no" they did not) and second, on a 0-100 continuous scale. Data were analyzed using an analysis of variance for both dependent variables, as well as a priori contrasts to make planned comparisons. As predicted, main effects were found for the presence of an alternative investment and magnitude of loss. However, no significant effect was found for monitoring. It was also hypothesized that the combination of the presence of an alternative investment, "high" monitoring and "high" magnitude of loss would be enough of a psychological deterrent to cause decision makers to stop the project, even though it was 90% complete. However, this prediction was not validated. Interestingly, though, the combination of the presence of an alternative investment, "high" magnitude of loss and "low" monitoring was enough to cause decision makers to stop the project at a level significantly less than by chance for the continuous dependent variable, and marginally significant less than by chance for the dichotomous dependent variable. Most importantly, these findings suggest for the first time that decision makers are willing to stop a project even though it is 90% complete.
622

An ultra-fast digital diffuse optical spectroscopic imaging system for neoadjuvant chemotherapy monitoring

Torjesen, Alyssa Ashley 05 November 2016 (has links)
Up to 20% of breast cancer patients who undergo presurgical (neoadjuvant) chemotherapy have no response to treatment. Standard-of-care imaging modalities, including MRI, CT, mammography, and ultrasound, measure anatomical features and tumor size that reveal response only after months of treatment. Recently, non-invasive, near-infrared optical markers have shown promise in indicating the efficacy of treatment at the outset of the chemotherapy treatment. For example, frequency domain Diffuse Optical Spectroscopic Imaging (DOSI) can be used to characterize the optical scattering and absorption properties of thick tissue, including breast tumors. These parameters can then be used to calculate tissue concentrations of chromophores, including oxyhemoglobin, deoxyhemoglobin, water, and lipids. Tumors differ in hemoglobin concentration, as compared with healthy background tissue, and changes in hemoglobin concentration during neoadjuvant chemotherapy have been shown to correlate with efficacy of treatment. Using DOSI early in treatment to measure chromophore concentrations may be a powerful tool for guiding neoadjuvant chemotherapy treatment. Previous frequency-domain DOSI systems have been limited by large device footprints, complex electronics, high costs, and slow acquisition speeds, all of which complicate access to patients in the clinical setting. In this work a new digital DOSI (dDOSI) system has been developed, which is relatively inexpensive and compact, allowing for use at the bedside, while providing unprecedented measurement speeds. The system builds on, and significantly advances, previous dDOSI setups developed by our group and, for the first time, utilizes hardware-integrated custom board-level direct digital synthesizers (DDS) and analog to digital converters (ADC) to generate and directly measure signals utilizing undersampling techniques. The dDOSI system takes high-speed optical measurements by utilizing wavelength multiplexing while sweeping through hundreds of modulation frequencies in tens of milliseconds. The new dDOSI system is fast, inexpensive, and compact without compromising accuracy and precision.
623

Rights Holders, Stakeholders, and Scientists: A Political Ecology of Ambient Environmental Monitoring in Alberta, Canada

Thill, Zackery 06 September 2018 (has links)
States increasingly rely on ambient environmental monitoring systems to provide information on environmental conditions in order to make science-based decisions on resource management. This kind of monitoring relies on a network of state and intergovernmental agencies to generate indexes, thresholds, and indicators to assess the status of air, water, and biodiversity. As a result, these thresholds and indexes generate representations of environmental change, and they establish acceptable limits on pollution. However, in settler states like Canada, there are often major gaps in how First Nations experience environmental change compared to the agencies that produce the science. In recent years, monitoring has taken on a new importance because the findings from these agencies contribute to understanding how industrial development impacts First Nations’ treaty rights. Many First Nation communities have called for greater say in government agencies and have advocated for indicators that represent both their basic environmental concerns and their treaty rights. Using oil sands monitoring agencies as a lens, this dissertation examines the politics of environmental knowledge production between Indigenous groups and the state. I employ the “logic of elimination” concept from settler colonialism studies to explore the extent to which Indigenous groups have been incorporated in research design, decision-making, and the establishment of environmental thresholds. I use interviews, participant observation, and a Q-method survey to develop an understanding how settler colonialism functions not only through policies and legislation, but also scientists’ positionalities. The findings from this research demonstrate that monitoring agencies have no uniform policies to guide how they work with First Nations. Because of this, agencies have continually engaged with First Nations as stakeholders—not rights holders. This designation places First Nations on the same level as other interest groups and limits their abilities to shape what is monitored and how thresholds are set. As a result, the stakeholder position offers few avenues for First Nations to ensure treaty rights are considered in monitoring activities. / 10000-01-01
624

Microstructural processes leading to fracture in nuclear graphites

Neighbour, Gareth Bryan January 1993 (has links)
No description available.
625

Monitoring the Effectiveness of Streambank Stabilization Projects in Northeast Kansas.

Benitez Nassar, Denisse Maria January 1900 (has links)
Master of Science / Department of Horticulture and Natural Resources / Charles J. Barden / Sedimentation of Federal reservoirs in Kansas has been identified as a critical issue affecting municipal and industrial water supplies, flood control, recreation, and aquatic life. Eroding streambanks are major sources of sediment. Many streambank stabilization projects have been installed over the past 20 years, but there has been very little follow-up monitoring of the effectiveness of these practices. The project goal is to quantify the environmental benefits of government-sponsored streambank stabilization and restoration projects in northeastern Kansas, with a focus on six sites in which tree ad rock revetments were installed. Several of the sites had stabilized reaches and similar un-stabilized reaches as controls. Macroinvertebrate bioassessments were conducted at two sites, on the Delaware River and Plum Creek on the Kickapoo reservation, to compare eroding and stabilized stream reaches. Biotic Index, Biological Monitoring Working Party (BMWP), Average Score per Taxon (ASPT), and Elmidae – Plecoptera – Trichoptera (EIPT) were calculated to compare the stabilized sites performance for water quality and aquatic habitat. The biological indices showed habitat quality on stabilized reaches compared to control reaches. Alfa diversity Shannon-Wiener and Simpson indices were calculated and improve in habitat quality and macroinvertebrate diversity was shown in stabilized reaches. Two new cedar revetments were established in 2017 on Little Grasshopper and Wolfley creeks. These cedar revetment installations resulted in heavy sediment deposits after high flow events with the revetments retaining 121 and 48 cubic meters, respectively. A novel method of using exposed roots was used successfully to quantify erosion on Axtell-Schmidt Dairy farm creek and Wolfley creek, where we found an average yearly erosion of 3.39 and 10.26 cm respectively. Other sites also showed reduced erosion on stabilized reaches and a development of vegetation cover along the riparian areas near the streams. Cedar revetments are shown to be a cost-effective stabilization method on smaller streams. Also, these practices and evaluation methods are a good opportunity for community and stakeholder involvement because it is possible to train community members in the monitoring practices. It is recommended to continue monitoring these sites to compare them with the designated control in order to document long-term effects.
626

Adolescents’ Perceptions of Parenting Practices and their Influence on Success, Academic Motivation, and School Belonging

Rubio, David, Jr. 23 March 2018 (has links)
Although academic motivation and school belonging positively influence student adjustment and experiences in school, early adolescence marks a time when motivation, belonging, and success in school tend to decline. Research has investigated ways that teachers and peers can support school success and student adjustment. However, there is less research on the role that parents play in supporting students’ success, motivation, and belonging in middle school. Additionally, most research examining the role of parents has focused on parenting styles rather than parenting practices (e.g., parental involvement and parental monitoring). Our understanding of the ways that specific parenting practices may support success, academic motivation, and school belonging is incomplete. Furthermore, studies rarely take into account adolescents’ own voices when studying the influence of parenting practices on student success, academic motivation, and school belonging. The purpose of this study was to explore which parenting practices adolescents at one large, urban, ethnically diverse middle school perceived as currently supporting and having the potential to increase their success in school, academic motivation, and school belonging. A secondary qualitative analysis of individual interviews with 18 middle school students who self-reported different levels of academic motivation was completed using the hybrid process of inductive and deductive thematic analysis (Fereday & Muir-Cochrane, 2006). This analysis process allowed for the use a priori codes and for the integration of emergent codes. The Contextual Model of Parenting; which incorporates parental involvement, parental motivation, and parental socialization goals; was used as the basis of the a priori codes. The findings indicated that participants perceived specific parenting practices as currently supportive and/or had the potential to increase their success, motivation, and belonging in school. Specifically, social-emotional monitoring emerged as a theme as currently supporting and most likely to increase participants’ academic motivation. Participants viewed the parental value, making school a priority, as currently supporting their success in school. Although participants did not identify any specific parenting practices that currently supported their school belonging, peer-based monitoring practices were perceived as ways parents could potentially increase school belonging. Some differences emerged among the different self-reported motivation levels, particularly for how parents supported motivation. Students with self-reported low levels of motivation reported that parents providing or withholding positive items or activities supported their motivation. Students with medium motivation voiced having their parents act as role models was supportive of motivation. Highly motivated students stated that words of support and encouragement from parents was a supportive practice for their motivation. Results demonstrated the need for further investigation into the role of social-emotional monitoring practices in supporting students’ success, motivation, and school belonging. In addition, result indicated the need for parents to be mindful of the social-emotional wellbeing of their children.
627

Vyhodnocení aktivity jezevce lesního (Meles meles) v okolí své nory / Activity of the badger (Meles meles) in a viccinity of its burrow

Jeřábek, František January 2016 (has links)
This master is theses describes the activity of the European badger (Meles meles) in the cadastral territory of Horní Studenec. The activity was monitored in relation to weather, time of sunrise and sunset and the moon phase in different seasons of a year. This thesis consists of two parts, practical and theoretical. The theoretical part is based on a literary research. The practical part analyzes data acquired by the author through a camera trap monitoring and personal observation at a particular badger warren. The outcome of this thesis is the finding that the following factors have influence on badger is behavior: lunar moon phase, daily minimum temperature and changes in external environment caused by human intervention.
628

Monitoring poškození dřevin okusem na kontrolních a srovnávacích plochách (KSP) na území lesní správy Loučná nad Desnou

Lenhart, Tomáš January 2015 (has links)
This thesis deals with a data processing about growth and browse damage at check and comparative areas. The data is evaluated by the method used by Forest Management Institute in the process of creation of Regional Plans of Forest Development and it is compared with my own detailed monitoring according CERMAK (2006). The results are further confronted with game records, namely the spring game numbers and the number of annual hunting. The data about growth and browse damage were collected at 28 check and comparative areas. The total browse damage of trees in the forest district Loučná nad Desnou was 42.2 %. The most damaged and at the same time the most occuring deciduous tree species in the forest district are common ash, sycamore maple and rowan. In case of common ash (Acer pseudoplatanus) reachs the browse damage 73 %. Among the most damaged coniferous species is silver fir (Abies alba) with browse damage up to 85 %.
629

Hodnocení toxicity průsakových vod ze skládky odpadů Kuchyňky

Studeníková, Petra January 2016 (has links)
Thesis on Evaluation of the toxicity of the water seepage from landfill Kuchyňky is engaged in legislation, waste management, statistical data in the beginning. Then there is a theoretical description of the process of landfill, division of landfills and characteristics of the basic methods of ecotoxicology. The next part is devoted to informations about landfill Zdounky Kuchyňky, its location, natural conditions and monitoring data on the landfill. Then the chapter is devoted to the description of the test of growth of duckweed (Lemna minor L.) on water seepage from landfill Kuchyňky. In the last part of the thesis there is the evaluation of the results of a toxicity test of water seepage and rainwater from landfill Kuchyňky.
630

Interferometric Methods for Seismic Monitoring in Industrial Environments

Dales, Philippe 19 October 2018 (has links)
As the global demand for energy and natural resources continues to increase so does our interaction with Earth's near surface through resource extraction and waste injection. In monitoring these interaction, seismology plays a central role. The focus of this work is on improving the detection and localization of seismic sources, a fundamental problem in seismology. After discussing the strengths and limitations of existing methods for source detection and localization, I develop a solution based on a beamforming approach that uses cross-correlation functions in a maximum likelihood search for sources of seismic energy. I call this method InterLoc, short for `interferometric locator', and apply it to data recorded at two active underground mines to demonstrate its effectiveness in monitoring both impulsive sources and persistent sources. Next, I demonstrate how persistent seismic sources, typically seen as contaminants, can be used directly to measure small changes in the medium between a source and either source-station pairs. This method relies on the ability to locate and monitor source activity and then use this information to identify and select cross-correlation functions to isolate each source of interest. From the resulting cross-correlations, it is possible to measure small temporal changes in the waveforms. To demonstrate this method, I show how ore-crushers can be used to track the growth of a block cave by measuring changes in traveltimes due to ray paths having to circumvent the growing cave. In the final chapter I focus on the development of a processing framework for the detection and location of microseismic events recorded on dense (or large-N) surface arrays. The proposed framework involves: (1) data reduction; (2) dividing the array into smaller sub-arrays; (3) waveform processing within fixed time windows; (4) stacking of time windows selected based on each potential origin time and source location; and (6) combining the output from all sub-arrays to infer detections and locations of sources. This methodology is validated with synthetic data built to emulate a real dataset from a 10,050 node survey to evaluate the suitability of land for carbon sequestration. Based on the presence of very strong coherent contaminating sources and low rock quality, I am only able to detect sources with moment magnitude greater than -0.5. In the five hours of data processed there is no positive detections suggesting this could be a good site for carbon storage. More work is needed to improve the detection threshold and quantify risk based on event location and magnitude. In summary, my work demonstrates how the interference (via cross-correlation) and stacking of seismic waveforms can be combined in different ways to create effective solutions for problems faced by today's industries.

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