• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1426
  • 157
  • 119
  • 111
  • 83
  • 77
  • 34
  • 21
  • 15
  • 11
  • 11
  • 11
  • 10
  • 9
  • 7
  • Tagged with
  • 2738
  • 2738
  • 894
  • 781
  • 677
  • 642
  • 354
  • 300
  • 297
  • 263
  • 236
  • 234
  • 202
  • 201
  • 199
  • 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.
271

The practice of leadership| A survey of National Park Service chief park rangers

Maciha, Mark Joseph 18 July 2014 (has links)
<p> The role of the national park ranger is to protect, conserve, and to provide for the enjoyment of our nation's heritage. Unfortunately, today's rangers are challenged with problems in the organizational leadership of the National Park Service. The agency is currently ranked in the bottom third of federal agencies in workplace health and leadership. </p><p> As some of the most visible leaders in the National Park Service, chief park rangers were queried through a descriptive qualitative design. The open-ended survey instrument was designed to answer the following two research questions: "Assuming that formal training in leadership influences successful leadership practice, what are the perceived results and outcomes of this training?" and "What are the factors, other than training, that influence an individual's desired practice of leadership?" A total of 29 chief park rangers of an eligible 51 chief park rangers in the Intermountain Region of the National Park Service responded to the survey conducted in January 2014. Their responses were categorized as to (a) the impact of the agency's training efforts on chief park rangers; (b) the barriers to the practice of leadership as experienced by chief park rangers; and (c) considerations for improvement in the leadership of the National Park Service. </p><p> The research concluded that training, although perceived to be limited in availability, was beneficial. However, training absent experience negatively influenced leadership practice. The predominant barriers to the desired practice of leadership were the lack of training, unfavorable organizational culture, and burdensome administrative practices. Although the survey was designed to focus on the issues of empowerment, fairness, senior leadership, and direct supervision, the respondents indicated that the barriers mentioned above were of primary concern rather than problems with these specific issues. The research suggested that the efforts of the National Park Service need to focus on enhancing leadership training program management and on initiating comprehensive reform of leadership practices to include active leadership development, enhanced accountability at all levels, and specific messaging from senior management. </p>
272

Quantifying the restorable water volume of Sierran meadows

Emmons, Jason Daniel 31 May 2014 (has links)
<p> The Sierra Nevada is estimated to provide over 66% of California's water supply, which is largely derived from snowmelt. Global climate warming is expected to result in a decrease in snow pack and an increase in melting rate, making the attenuation of snowmelt by any means, an important ecosystem service for ensuring water availability. Montane meadows are dispersed throughout the mountain range providing wildlife habitat, water filtration, and water storage. Despite the important role of meadows in the Sierra Nevada, the majority are degraded from stream incision, which increases volume outflows and reduces overbank flooding, thus reducing infiltration and potential water storage. Restoration of meadow stream channels would therefore improve hydrological functioning, including increased water storage. The potential water holding capacity of restored meadows has yet to be quantified, thus this research seeks to address this knowledge gap by estimating the restorable water volume due to stream incision. More than 17,000 meadows were analyzed by categorizing their erosion potential using channel slope and soil texture, ultimately resulting in six general erodibility types. Field measurements of over 100 meadows, stratified by latitude, elevation, and geologic substrate, were then taken and analyzed for each erodibility type to determine average depth of incision. Restorable water volume was then quantified as a function of water holding capacity of the soil, meadow area and incised depth. Total restorable water volume across meadows in the Sierra Nevada was found to be 120 x 10<sup>6</sup>m<sup>3</sup>, or approximately 97,000 acre-feet. Using 95% confidence intervals for incised depth, the upper and lower bounds of the total restorable water volume were found to be 107 x 10<sup>6</sup>m<sup> 3</sup> &ndash; 140 x 10<sup>6</sup>m<sup>3</sup>. Though this estimate of restorable water volume is small in regards to the storage capacity of typical California reservoirs, restoration of Sierra Nevada meadows remains an important objective. Storage of water in meadows benefits California wildlife, potentially attenuates floods, and elevates base flows, which can ease effects to the spring snowmelt recession from the expected decline in Sierran snowpack with atmospheric warming.</p>
273

Water Quality and Quantity in Intermittent and Continuous Piped Water Supplies in Hubli-Dharwad, India

Kumpel, Emily 31 May 2014 (has links)
<p> In at least 45 low- and middle-income countries, piped water systems deliver water for limited durations. Few data are available of the impact of intermittent water supply (IWS) on the water quality and quantity delivered to households. This thesis examines the impact of intermittently supplied piped water on the quality and quantity of water delivered to residential taps in Hubli-Dharwad, India, when compared to continuous piped water supply. A framework for understanding the pathways through which IWS can impact water quality is first developed. The extent to which contamination occurs in Hubli-Dharwad is quantified by comparing microbial water quality throughout the distribution system in an intermittent system and a continuous system in the same city. The mechanisms affecting water quality in the IWS network in Hubli-Dharwad are identified by measuring changes in water quality over time using continuous measurements from pressure and physico-chemical sensors paired with grab samples tested for indicator bacteria. In the final chapter, a new method of measuring household water consumption in an IWS when supply durations are limited and few metered data are available is developed. This thesis showed that the intermittent supply was frequently subject to contamination in the distribution system and that households with intermittent supply consumed limited quantities of water. While these results demonstrated that converting to a continuous water supply can improve water quality when compared to intermittent supply, this conversion may not be possible in the near future for resource-constrained towns and cities. This thesis contributes to knowledge of the mechanisms causing contamination and constricting water access in IWS systems, which can help improve systems to ensure that people with piped water receive water that is reliable, safe, and sufficient.</p>
274

Determining the relative influence of mental pollutants in Newport and Laguna beach seawater on the Giant Kelp (Macrocystis pyrifera) populations of Crystal Cove State Park by analysis of sieve sap metals

Burnett, Danielle Lee 29 April 2014 (has links)
<p> The abstract is not available from PDF copy and paste.</p>
275

Adaptive Solutions to Resource Provisioning and Task Allocation Problems for Cloud Computing

Desmarais, Ronald J. 23 December 2013 (has links)
With the emergence of the cloud computing paradigm, we can now provide dynamic resource provisioning at unprecedented levels of scalability. This flexibility constitutes a rich environment for researchers to experiment with new designs. Such experimental novel designs can take advantage of adaptation, controllability, self- configuration, and scheduling techniques to provide improved resource utilization while achieving service level agreements. This dissertation uses control and scheduling theories to develop new designs to improve resource utilization and service level agreement satisfaction. We optimize resource provisioning using the Cutting Stock problem formulation and control theory within feedback frameworks. We introduce a model-based method of control to manipulate the scheduling problem’s formulation model to achieve desired results. We also present a control based method using Kalman filters for admission control. Finally, we present two case studies — the Yakkit media social application and the Rigi Cloud testbed for deploying virtual ma- chine experiments. The results of our investigations demonstrate that our approaches and techniques can optimize resource utilization, decrease service level agreement violations, and provide scheduling guarantees. / Graduate / 0790 / 0984 / rd@uvic.ca
276

Benthic macroinvertebrates in Uvas Creek, California, downstream of a reservoir

Foster, Carole A. 20 February 2015 (has links)
<p> I sampled macroinvertebrates in May, July, and October 2008 in Uvas Creek, a reservoir-regulated stream in south Santa Clara County, California, to assess what factors (including canopy closure, turbidity, and stream flow) downstream of the reservoir were related to food availability for rearing juvenile Steelhead (Oncorhynchus mykiss). I found benthic and drifting macroinvertebrate biomass was considerably greater during most months in the more open-canopied two sites in the downstream reach as compared to the densely shaded, more turbid and silty two sites in the upstream reach. Abundance of important drifting aquatic invertebrates in May (chironomids, simuliids, and baetids) was proportional to benthic abundance, but large hydropsychids were relatively scarce in the drift. Terrestrial drift abundance correlated with canopy density, but differences were small compared to the substantial increase in aquatic drift in sunnier sites. Thinning of the canopy at select locations and reduction of sediment input to Uvas Creek and its tributaries due to vineyard and other operations could increase benthic macroinvertebrate productivity in the upstream reach, which would increase food availability for rearing juvenile Steelhead.</p>
277

Hydrologic dynamics control dissolved organic matter export from watersheds| Fields-scale processes in a small, artificially drained agricultural catchment, and patterns across ecosystems

Bellmore, Rebecca Anne 07 March 2015 (has links)
<p>Dissolved organic matter (DOM) is an important component of nutrient cycling and energy transfer within and between ecosystems. Understanding controls over the magnitude and quality of DOM that is transferred from soils to surface water is needed to better characterize the terrestrial-aquatic carbon flux and effects of terrestrial DOM on downstream ecosystems. A meta-analysis of the response of in-stream dissolved organic nitrogen concentration (DON) to high flow events indicates that DON typically increases with flow across a wide range of ecosystem types, likely as novel DOM sources in the landscape are mobilized and transported to streams and rivers. Mechanisms controlling DOM export, including dissolved organic carbon (DOC) and DON concentrations and the quality of DOM, were examined in a small agricultural catchment in eastern Washington State. In the soil column, DOC concentration declined and source of DOM shifted from humic-like and plant-derived to microbially-derived with depth through the profile. Across seasons and years, DOM exported via drain discharge during low flows resembled that found deep in the soil profile, and DOM exported during high flows suggests topsoil and litter sources contribute to export. A simple mixing model suggests that litter leachate can contribute over 50% of DOM during peak flow. Based on modeled contributions of litter, topsoil and subsoil DOM during storm events, DOC concentration is over-predicted, except for peak flows, suggesting removal via sorption and/or microbial decomposition in the soil column control DOC export on the timescale of events. Although the character of exported DOM shifts with flow conditions, laboratory incubations suggest bioavailability to the stream sediment microbial community is consistently low, with a maximum of 7% loss over 6 days, indicating exported DOM is likely transported beyond the immediate stream reach. An analysis of anticipated effects of climate change on the flow regime in the catchment projects the wettest years to become more variable, with non-linear effects on the magnitude of DOC export. Finally I explore how climate change assessments can be incorporated into nonpoint source nutrient management plans, despite current uncertainty about the magnitude and timeframe of climate effects on nutrient loading.
278

Review of factors affecting sustainability in the universities

Ajilian, Hosna 19 February 2015 (has links)
<p> Understanding the factors which influence adopting sustainability practices in IHE is an important issue to develop more effective sustainability's methods and policies. The focus of this research is to find out a meaningful relationship between adopting sustainability practices and some of the characteristics of institutions of higher education (IHE). IHE can be considered as the best place to promote sustainability and develop the culture of sustainability in society. Thus, this research is conducted to help developing sustainability in IHE which have significant direct and indirect impact on society and the environment. </p><p> First, the sustainability letter grades were derived from "Greenreportcard.org" which have been produced based on an evaluation of each school in nine main categories including: Administration, Climate Change &amp; Energy, Food &amp; Recycling, etc. In the next step, the characteristics of IHE as explanatory variables were chosen from "The Integrated Postsecondary Education Data System" (IPEDS) and respective database was implemented in STATA Software. Finally, the "ordered-Probit Model" is used through STATA to analyze the impact of some IHE's factor on adopting sustainability practices on campus. </p><p> The results of this analysis indicate that variables related to "Financial support" category are the most influential factors in determining the sustainability status of the university. "The university features" with two significant variables for "Selectivity" and "Top 50 LA" can be classified as the second influential category in this table, although the "Student influence" is also eligible to be ranked as the second important factor. Finally, the "Location feature" of university was determined with the least influential impact on the sustainability of campuses.</p>
279

A cultural analysis of payment-systems-in-use in three chemical companies

Bell, Emma January 1999 (has links)
No description available.
280

Water Use, Virtual Water and Water Footprints| Economic Modeling and Policy Analyses

Fadali, Elizabeth 26 February 2014 (has links)
<p> The theme that binds together the four papers in this dissertation is the tracking of physical quantities of water used by industries in the economy, and an exploration of whether and how this tracking could be helpful in informing water policies, as applied to the state of Nevada or sub-regions of Nevada. The concept of water footprints has been wildly popular in disciplines outside of economics and has been used to help make policy decisions normally considered to lie within the economist's realm. Yet many economists shun 'footprints' in general and water footprints in particular, seeing them as descriptive methods that have little or nothing to add to policy analysis. This thesis attempts to bridge a gap between economists, engineers and planners and the popular imagination about what economic concepts footprints are related to and how they can best be used in policy analysis.</p>

Page generated in 0.0884 seconds