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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.
201

Identifying Key Factors for the Implementation and Maintenance of Green Stormwater Infrastructure

Delgrosso, Zack Lee 25 May 2018 (has links)
Construction and maintenance can have huge implications on the long-term functioning of GSI facilities. GSI facilities investigated were bioretention, permeable pavement, sand filters, infiltration trenches, and vegetated swales. This study first highlights the most important construction and maintenance items based on relevant studies and state stormwater manuals. Fairfax County, VA was used as a case study to evaluate the County's current stormwater program and illuminate common maintenance issues found for each GSI type. Data analysis of 3141 inspection records illustrated particular deficiencies for each GSI type and that there are differences between public and private facilities, most likely depending on site conditions and frequency of routine maintenance. Sediment accumulation was found to be the most common maintenance issue (27.8% of inspections), supporting the importance of adequate pretreatment and good housekeeping when implementing GSI. The Northern Virginia Soil and Water Conservation District (NVSWCD) performed a study surveying 63 public bioretention facilities in which they measured ponding depth, filter media depth, ponding area, and infiltration rates. The NVSWCD concluded that deficiencies found in facilities could mostly be attributed to inadequacies during construction. By comparing current post-construction inspections performed by the County to the NVSWCD data, it was found that these County inspections are failing to detect these inadequacies in bioretention facilities from improper construction. It is recommended that MS4s thoroughly record and track construction and post-construction inspection items to improve the longevity of its facilities and better inform future decision making regarding GSI. / Master of Science
202

The Role of Program Evaluations in Improving and Sustaining State-Supported School Counseling Programs: A Cross Case Analysis of Best Practices

Martin, Ian Monteg 01 September 2009 (has links)
Recent work has shown that many state supported school counseling programs have not developed working statewide program evaluation schemas. This study examined two exemplary examples of state level program evaluation. Mixed-method case studies were created and then analyzed across cases to reveal common themes and best practices. The findings indicated that these cases were able to build statewide evaluation capacity within very different contexts.
203

Is economic value added (eva) the best way to assemble a portfolio?

Pataky, Tamas 01 December 2012 (has links)
In search of a better investment metric, researchers began to study Economic Value Added, or EVA, which was introduced in 1991 by Stern Stewart & Co in their book, "The Quest for Value" (Turvey, 2000). Stern Stewart & Co devised EVA as a better alternative to evaluate investment projects within the corporate finance field, later to be considered for use as a performance metric for investor use. A wide array of multinational corporations, such as Coca-Cola, Briggs and Stratton, and AT&T adopted the EVA method, which led to EVA's worldwide acclaim. Several points in the study reveal that EVA does not offer less risk, higher returns, and more adaptability for an investor. In fact, EVA underperformed the traditional portfolio performance metrics in key measurements including mean returns, and confidence intervals. EVA is a difficult performance metric to calculate, with several complex components that can be calculated in several different ways such as NOPAT, cost of equity, and cost of debt. Any information that is inaccurate or lacking can significantly impact the outcomes. Traditional performance metrics, on the other hand, such as ROA, ROE, and E/P are simple to calculate with few components, and only one way to calculate them.
204

Evaluation of the efficacy of different best management practices under current and future climate regimes in Ludlow watershed

Fan, Rong 16 October 2015 (has links)
No description available.
205

Best Systemic Practices for the Management of Deaf Suspects, Defendants and Offenders

Shine, Beau 27 May 2016 (has links)
No description available.
206

Sediment Delivery Ratios and Areas of Forest Operational Features by Physiographic Groupings in the Southeastern U.S.

Horton, Celeste Nichole 15 June 2021 (has links)
Forests of the Southeastern United States produce approximately 12% of all the world's wood products and represent 40% of all U.S. timberland, thus emphasizing the importance of Southeast in support of the United States' role as the world's largest timber producer. Producing such quantities of timber requires a substantial areas of forest harvest operations, which have the potential to disturb soils, facilitate erosion and potentially reduce water quality. Harvest sites routinely contain operational features such as skid trails, harvest areas, haul roads, decks/landings and stream crossings, all of which have the potential to influence erosion and sediment deposition in streams. Forestry best management practices (BMPs) were created to minimize the effects of harvesting operations on sedimentation and are implemented at varying levels throughout the Southeastern U.S. We quantified the area of these features on 111 recent harvest sites throughout 11 Southeastern states and three physiographic groupings (Mountains, Piedmont, Coastal Plain). No significant differences were found between the groupings with regard to the percent of area occupied by each operational feature. Decks, haul roads, skid trails, and stream crossings comprised an average of 1.43%, 3.21%, 7.03%, and 0.19% of the harvest operations. Roads, decks, skid trails, and structures were combined into an access feature category. These combined access features occupied 13.0% of harvests in the Mountains, 10.2% in the Piedmont, and 10.4% in the Coastal Plain (10.4%). A companion study was developed to trap sediment delivered to the stream and quantify the sediment delivery ratios (SDRs) on a subset of harvests sites in order to determine the average amount of eroded material that could reach a stream from each specific operational feature following a harvest. Across all groupings, stream crossings had the highest average SDR (34.32%), while skid trails had the second highest SDR (21.04%). Substantial site variability resulted in large SDR differences with few meaningful significant differences, but stream crossings, skid trails, and haul roads had sufficiently high sediment delivery ratios across all groupings to warrant additional BMP focus on these areas. / Master of Science / The Southeastern United States is a major producer of forests and forest products, comprising about 40% of US timberland and 12% of global wood products. Support of this industry requires that over 4 million acres of forests are harvested annually across the southeastern U.S. and improper or under usage of forestry best management practices could result in soil erosion and subsequent transport to streams as sediment. Previous research indicates that different operational and access features found on logging sites have different erosion rates yet little data exists which document the percentages of erosion that is delivered as sediment to streams. Skid trails (trails that forestry equipment use within a harvesting operation) compromised the largest access feature average percent area (second to harvest area), followed by haul roads, then decks (area where equipment is kept and logs are processed and loaded), and finally stream crossings with the smallest average area. Stream crossings, skid trails and haul roads consistently had the highest average sediment delivery ratios for all groupings combined. However, substantial site variability resulted in large sediment delivery ratio differences with few meaningful significant differences.
207

Building a knowledge based simulation optimization system with discovery learning

Siochi, Fernando C. 06 June 2008 (has links)
Simulation optimization is a developing research area whereby a set of input conditions is sought that produce a desirable output (or outputs) to a simulation model. Although many approaches to simulation optimization have been developed, the research area is by no means mature. This research makes three contributions in the area of simulation optimization. The first is fundamental in that it examines simulation outputs, called "response surfaces," and notes their behavior. In particular both point and region estimates are studied for different response surfaces: Conclusions are developed that indicate when and where simulation-optimization techniques such as Response Surface Methodology should be applied. The second contribution provides assistance in selecting a region to begin a simulation-optimization search. The new method is based upon the artificial intelligence based approach best-first search. Two examples of the method are given. The final contribution of this research expands upon the ideas by Crouch for building a "Learner" to improve heuristics in simulation over time. The particular case of parameter-modification learning is developed and illustrated by example. The dissertation concludes with limitations and suggestions for future work. / Ph. D.
208

Effects of Forested Streamside Management Zone Widths and Thinning on Carbon Dynamics and Benthic Macroinvertebrates for Pine Plantations in the Piedmont of Virginia

Wadl, Erica Fritz 30 December 2008 (has links)
To protect the integrity of the United State's waters, the Federal Water Pollution Control Act of 1972 promoted the establishment of Best Management Practices (BMPs) for forestry. A commonly used BMP is the reservation of Streamside Management Zones (SMZs). In this study the effectiveness of three different SMZ widths, 30.5 m (100 ft), 15.3 m (50 ft), and 7.6 m (25 ft), as well as thinning in 15.3 m SMZs were studied. The objectives of the study were to determine the effects these SMZ treatments had on carbon pools, carbon fluxes and environmental conditions in the SMZ. The benthic macroinvertebrate populations present within the stream were also examined because of their relationship to ecosystem carbon dynamics. Carbon storage in plant communities, litter layer, soil (upper 10 cm), and total organic carbon present (TOC) within streams were measured and quantified. Total CO₂ efflux and the major environmental drivers of soil CO₂ efflux, soil moisture and soil temperature, were monitored along a single transect within each SMZ. This study showed that carbon dynamics and stream biota (benthic macroinvertebrates) were not adversely effected by more narrow SMZ width and thinning within the SMZ. SMZ width did affect soil temperature, one of the environmental drivers affecting soil respiration. Based on these short-term results a 15.3 m SMZ with thinning or without thinning appears adequate to prevent changes in ecosystem function and water quality for forest applications. / Master of Science
209

Effect of Golf Course Turfgrass Management on Water Quality of Non-tidal Streams in the Chesapeake Bay Watershed

Wilson, Chantel 09 April 2015 (has links)
Turfgrass management activities on golf courses have been identified as a possible source of Chesapeake Bay nutrient pollution. Total Maximum Daily Load goals are in place to reduce nutrient amounts entering the Bay. Dissertation investigations include (1) the role of golf course turfgrass management in nutrient deposition or attenuation in local streams, (2) estimations of total nitrogen (N) discharging to the watershed from stream outlet points as a function of land use and watershed area, and (3) other factors potentially affecting water quality on golf courses, including soil characteristics and use of best management practices (BMPs). Total N, nitrate-N, ammonium-N, phosphate-phosphorus (P), streamwater temperature, specific conductance (SpC), pH and dissolved oxygen (DO) were sampled at 12-14 golf course stream sites in the James River and Roanoke River watersheds during baseflow conditions. Discharge was determined at outflow locations. Unit-area loads (UALs) were calculated from monitoring data. These UALs were then compared to UALs from Chesapeake Bay Watershed Model land use acreages and simulated loads for corresponding watershed segments. Virginia golf course superintendents were also surveyed to determine BMP use. No consistent impairment trends were detected for streamwater temperature, SpC, pH, or DO at any of the sites. Outflow NO3-N was below the 10 mg L-1 EPA drinking water standard. However, some sites may be at increased risk for benthic impairment with total N concentrations >2 mg L-1, as suggested by VADEQ. Significant increases in nitrate-N at OUT locations were measured at four sites, whereas decreases were measured at two sites. Ammonium-N significantly decreased at two sites. Golf course N UALs calculated from baseflow monitoring were lower than or similar to UALs estimated for forested areas in the associated watershed segment at seven out of the 12 sites. Golf course UALs ranged from 1.3-87 kg N ha-1 yr-1. Twenty-one of 32 surveyed BMPs had an adoption rate ≥50% among survey respondents. In most cases, presence of golf courses generally does not appear to significantly degrade baseflow water quality of streams in this study. Management level appears to be an influencing factor on water quality and concerns may be heightened in urban areas. / Ph. D.
210

Assessing the Impact of Writing Centers on Student Writing

Lama, Prabin Tshering 30 April 2018 (has links)
This study assesses the influence of writing center tutorials on student writing and presents tutoring best practices. Writing center scholars have emphasized the need for evidence-based studies to understand how one-on-one tutorials influence student writing practices. After examining twenty tutorial recordings along with their pre-and post-intervention drafts in two state universities (ten in each university), the author traced the influence of writing center tutorials on students' post-session revisions and identified tutoring best practices. The findings show that all the twenty students included in the study followed up on the issues addressed in their tutorials, in some form or the other, in their post-session drafts. In terms of tutoring strategies, the findings revealed that although most of the tutors in the study could identify and speak about global concerns (i.e. development, structure, purpose, audience), many lacked specific strategies to address these concerns effectively. To address this concern, this study identifies tutoring best practices related to global concerns. Furthermore, the findings also revealed that the tutors faced challenges navigating the directive/non-directive continuum of tutoring. To address this concern, this study presents tutoring best practices to demonstrate how tutors can shift flexible between directive and non-directive strategies during a session. / Ph. D.

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