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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.
341

The Impact of Web-Based Tutorials in One Corporation's Transition to a Blended Learning Environment

Boyd, Michelle Anne 21 June 2008 (has links) (PDF)
ELM Resources, a not-for-profit, mutual-benefit corporation, provides web-based transmission and data translation services for student loan data between loan providers and schools/universities. This corporation has a relatively new training staff of five to seven employees and over 1,800 client organizations. Because of the heavy demands placed on the training staff, ELM training administrators sought alternatives to their current training program of onsite training and web conferencing. Blended learning was identified as one possible solution. In this project, blended learning is defined as using a combination of face-to-face training and technology-delivered training. By adding web-based, on-demand tutorials, along with other training media, ELM hoped to increase access to training while keeping costs low. This project explores the impact of these tutorials on ELM and its clients. Reported are an interview with the Director of Training and several surveys distributed to school staff, lenders, and ELM training specialists. A critique of the project addresses the need for future research to collect performance data. Evaluation results indicate that the changes to the training program have established a positive relationship between ELM and its clients, and have given ELM a definite competitive edge. The advantages especially noted in the evaluation results include the usefulness of the tutorials as both a reinforcement of previous training and a self-testing tool, their brief and highly visual format which teaches one process at a time, and the convenience in accessing and using the tutorials. Disadvantages include the tutorial's inherent impersonal nature, the loss of the ability to ask questions, and lack of optional narration. This paper discusses unanticipated benefits to the trainers, such as the use of the tutorials within face-to-face training sessions, and to other ELM staff members, including Help Desk personnel. The decrease in training-related Help Desk calls after the introduction of the training changes suggests a positive impact on learning.
342

Effects Of Orthophosphate Corrosion Inhibitor In Blended Water Quality Environments

Stone, Erica 01 January 2008 (has links)
This study evaluated the effects of orthophosphate (OP) inhibitor addition on iron, copper, and lead corrosion on coupons exposed to different blends of groundwater, surface water, and desalinated seawater. The effectiveness of OP inhibitor addition on iron, copper, and lead release was analyzed by statistical comparison between OP treated and untreated pilot distribution systems (PDS). Four different doses of OP inhibitor, ranging from zero (control) to 2 mg/L as P, were investigated and non-linear empirical models were developed to predict iron, copper, and lead release from the water quality and OP doses. Surface characterization evaluations were conducted using X-ray Photoelectron Spectroscopy (XPS) analyses for each iron, galvanized steel, copper, and lead/tin coupon tested. Also, a theoretical thermodynamic model was developed and used to validate the controlling solid phases determined by XPS. A comparison of the effects of phosphate-based corrosion inhibitor addition on iron, copper, and lead release from the PDSs exposed to the different blends was also conducted. Three phosphate-based corrosion inhibitors were employed; blended orthophosphate (BOP), orthophosphate (OP), and zinc orthophosphate (ZOP). Non-linear empirical models were developed to predict iron, copper, and lead release from each PDS treated with different doses of inhibitor ranging from zero (control) to 2 mg/L as P. The predictive models were developed using water quality parameters as well as the inhibitor dose. Using these empirical models, simulation of the water quality of different blends with varying alkalinity and pH were used to compare the inhibitors performance for remaining in compliance for iron, copper and lead release. OP inhibitor addition was found to offer limited improvement of iron release for the OP dosages evaluated for the water blends evaluated compared to pH adjustment alone. Empirical models showed increased total phosphorus, pH, and alkalinity reduced iron release while increased silica, chloride, sulfate, and temperature contributed to iron release. Thermodynamic modeling suggested that FePO4 is the controlling solid that forms on iron and galvanized steel surfaces, regardless of blend, when OP inhibitor is added for corrosion control. While FePO4 does not offer much control of the iron release from the cast iron surfaces, it does offer protection of the galvanized steel surfaces reducing zinc release. OP inhibitor addition was found to reduce copper release for the OP dosages evaluated for the water blends evaluated compared to pH adjustment alone. Empirical models showed increases in total phosphorus, silica, and pH reduced copper release while increased alkalinity and chloride contributed to copper release. Thermodynamic modeling suggested that Cu3(PO4)2·2H2O is the controlling solid that forms on copper surfaces, regardless of blend, when OP inhibitor is added for corrosion control. OP inhibitor addition was found to reduce lead release for the OP dosages evaluated for the water blends evaluated compared to pH adjustment alone. Empirical models showed increased total phosphorus and pH reduced lead release while increased alkalinity, chloride, and temperature contributed to lead release. Thermodynamic modeling suggested that hydroxypyromorphite is the controlling solid that forms on lead surfaces, regardless of blend, when OP inhibitor is added for corrosion control. The comparison of phosphate-based inhibitors found increasing pH to reduce iron, copper, and lead metal release, while increasing alkalinity was shown to reduce iron release but increase copper and lead release. The ZOP inhibitor was not predicted by the empirical models to perform as well as BOP and OP at the low dose of 0.5 mg/L as P for iron control, and the OP inhibitor was not predicted to perform as well as BOP and ZOP at the low dose of 0.5 mg/L as P for lead control. The three inhibitors evaluated performed similarly for copper control. Therefore, BOP inhibitor showed the lowest metal release at the low dose of 0.5 mg/L as P for control of iron, copper, and lead corrosion.
343

Multidisciplinary Design Optimization of Low-Noise Transport Aircraft

Leifsson, Leifur Thor 04 April 2006 (has links)
The objective of this research is to examine how to design low-noise transport aircraft using Multidisciplinary Design Optimization (MDO). The subject is approached by designing for low-noise both implicitly and explicitly. The explicit design approach involves optimizing an aircraft while explicitly constraining the noise level. An MDO framework capable of optimizing both a cantilever wing and a Strut-Braced-Wing (SBW) aircraft was developed. The framework employs aircraft analysis codes previously developed at the Multidisciplinary Design and Analysis (MAD) Center at Virginia Tech (VT). These codes have been improved here to provide more detailed and realistic analysis. The Aircraft Noise Prediction Program (ANOPP) is used for airframe noise analysis. The objective is to use the MDO framework to design aircraft for low-airframe-noise at the approach conditions and quantify the change in weight and performance with respect to a traditionally designed aircraft. The results show that reducing airframe noise by reducing approach speed alone, will not provide significant noise reduction without a large performance and weight penalty. Therefore, more dramatic changes to the aircraft design are needed to achieve a significant airframe noise reduction. Another study showed that the trailing-edge (TE) flap can be eliminated, as well as all the noise associated with that device, without incurring a significant weight and performance penalty. To achieve approximately 10 EPNdB TE flap noise reduction the flap area was reduced by 82% while the wing reference area was increased by 12.4% and the angle of attack increased from 7.6 degrees to 12.1 degrees to meet the required lift at approach. The wing span increased by approximately 2.2%. Since the flap area is being minimized, the wing weight suffers only about a 2,000 lb penalty. The increase in wing span provides a reduction in induced drag to balance the increased parasite drag due to a lower wing aspect ratio. As a result, the aircraft has been designed to have minimal TE flaps without any significant performance penalty. If noise due to the leading-edge (LE) slats and landing gear are reduced, which is currently being pursued, the elimination of the flap will be very significant as the clean wing noise will be the next 'noise barrier'. Lastly, a comparison showed that SBW aircraft can be designed to be 10% lighter and require 15% less fuel than cantilever wing aircraft. Furthermore, an airframe noise analysis showed that SBW aircraft with short fuselage-mounted landing gear could have similar or potentially a lower airframe noise level than comparable cantilever wing aircraft. The implicit design approach involves selecting a configuration that supports a low-noise operation, and optimizing for performance. A Blended-Wing-Body (BWB) transport aircraft has the potential for significant reduction in environmental emissions and noise compared to a conventional transport aircraft. A BWB with distributed propulsion was selected as the configuration for the implicit low-noise design in this research. An MDO framework previously developed at the MAD Center at Virginia Tech has been refined to give more accurate and realistic aircraft designs. To study the effects of distributed propulsion, two different BWB configurations were optimized. A conventional propulsion BWB with four pylon mounted engines and two versions of a distributed propulsion BWB with eight boundary layer ingestion inlet engines. A 'conservative' distributed propulsion BWB design with a 20% duct weight factor and a 95% duct efficiency, and an 'optimistic' distributed propulsion BWB design with a 10% duct weight factor and a 97% duct efficiency were studied. The results show that 65% of the possible savings due to 'filling in' the wake are required for the 'optimistic' distributed propulsion BWB design to have comparable $TOGW$ as the conventional propulsion BWB, and 100% savings are required for the 'conservative' design. Therefore, considering weight alone, this may not be an attractive concept. Although a significant weight penalty is associated with the distributed propulsion system presented in this study, other characteristics need to be considered when evaluating the overall effects. Potential benefits of distributed propulsion are, for example, reduced propulsion system noise, improved safety due to engine redundancy, a less critical engine-out condition, gust load/flutter alleviation, and increased affordability due to smaller, easily-interchangeable engines. / Ph. D.
344

Preliminary Power Analysis of an Unmanned Aerial Vehicle : Featuring Integrated Electric Ducted Fans

Yu, Conny, During, Ruben January 2022 (has links)
With increasing focus on climate change more research for net-zero emission are being made in the aviation industry.This project focuses on electric propulsion on a unmanned aerial vehicle (UAV) with a blended wing body (BWB) design. More specifically finding a solution for a propulsion system using electric ducted fan (EDF) engines for a scaled version of the KTH Aerospace project Green Raven. The system consists of a powerplant and power supply i.e engine(s) and a sufficient battery package. The goal is to find a solution to power this 7 kg aerial vehicle for 60 minutes with a consistent cruising speed of 30 m/s. To accomplish this an understanding of thrust and drag profile is essential in order to determine the requirements for the EDFs. Understanding the limitations of the scaled Green Raven is also necessary in order to provide a feasible solution for power supply. The result is to use 2x 50 mm EDF engines providing a total thrust of 16.7 Newtons that is integrated in the main body. To supply these engines two battery sets (one per EDF) composed of three different battery types have been chosen, giving a total capacity of 24 000 mAh for one hour flight time. This propulsion setup fulfils the requirements, though not without flaws because of the choice of integrating the EDFs. An alternative solution would be having the engines externally mounted in order to free up the space in the body for more efficient batteries.
345

Strategic Blended Learning: 9-12 Teacher Perceptions of Digital Engagement Post COVID-19

Weaver, Brandon D 01 December 2023 (has links) (PDF)
This quantitative study examined teacher perceptions on the relationship between technology, student academic behaviors, and performance in blended 9th-12th grade settings through pre-COVID-19 Pandemic and post-COVID-19 Pandemic learning experiences. This replicate study explored the relationship between teacher perceptions of student motivation and student autonomy and their relation to technology implementation in face-to-face instruction and blended learning environments. Particularly, this study analyzed how student motivation and student autonomy were affected by blended learning technologies and teaching strategies introduced after the onset of the COVID-19 Pandemic. Data were examined to investigate teacher perceptions on the relationship between technology, student academic behaviors, and performance in blended learning 9th-12th grade settings through pre-COVID-19 Pandemic and post-COVID-19 Pandemic learning experiences in two east Tennessee school districts. Participants of this study included 42 high school teachers post-COVID-19 Pandemic in 2023 and 75 high school teachers pre-COVID-19 Pandemic in 2020 within two school districts in east Tennessee. Statistical analyses of the data revealed significance on participant teacher perceptions of student motivation and student autonomy. Findings did not correlate to the original study. The research revealed there was a significant difference in teacher perceptions of student autonomy in the face-to-face instructional setting. Findings indicated teacher perceptions of student motivation were significantly higher post-COVID-19 Pandemic compared to pre-COVID-19 Pandemic.
346

Measuring The Information Literacy of School Stakeholders in Implementing Blended Learning in High Schools in The State of Kuwait to Propose a School Management System. Examining the level of information literacy of stakeholders in High schools and to propose a new school management system to achieve the best implementation of information literacy and blended learning practices

AlQaoud, Fatima N.H. January 2022 (has links)
Information Literacy (IL) has been implemented among workers in schools in recent years in order to enhance workers’ skills and competencies through the utilisation of technology in education. To implement a sustainable IL system, the building of an IT infrastructure is required including the provision of PCs and network access, enabling students to connect to the internet during class time in order to access educational web-based content as well as to share discussions about subjects with their peers in and out of the class. Assessing the level of information literacy (IL) of stakeholders will assist in creating a new proposed school management system (SMS) to be used among them in the future. This will encourage teachers to use blended learning approach for teaching their students. Therefore, it is important to examine the IL of stakeholders (principal, head of division, teacher) in Kuwait to increase their skills and competencies which will lead to greater innovation in future developments. This work aims at assessing information literacy level of stakeholders, their skills and competencies in utilising technology in a workplace environment, which will assist the researcher to create a new school system. In addition, this work presents a new proposed school management system (SMS) for stakeholders in the current educational system of high schools in Kuwait, therefore, applying the BL approach in order to achieve a high quality of students' learning outcomes.
347

Aerodynamic Analysis of a Blended Wing Body UAV

Harrisson, Oliver January 2022 (has links)
The focus of this thesis is to analyse the flight characteristics of the blended wingbody (BWB) unmanned aerial vehicle (UAV) Green Raven currently being developed by students at the Royal Institute of Technology (KTH) in Stockholm,Sweden. The purpose of evaluating a BWB aircraft is due to its potential increasein fuel efficiency and payload compared to conventional aircrafts which would enable more sustainable flights. The analysis is conducted in ANSYS Fluent 2020R2 where the goals are to extrapolate lift, drag and pitching moment coefficients,aerodynamic efficiency and evaluate stall patterns. The analysis is conducted with free stream velocities from 5 m/s to 40 m/s with5 m/s increments at angles of attack from −4◦ to stall plus 4◦. The result of thisthesis is that an analysis have not been able to be conducted due to a lack ofcomputational power. Thusly, the conclusion to this thesis is that to be able toperform a complete analysis of the Green Raven, a more powerful computer needsto be used.
348

A Phenomenological Exploration of the Experience of Parenting Half-Siblings Within a Blended Family

Josephsen, Nicole RR 16 April 2015 (has links)
No description available.
349

The effect of group mode and time in course on frequency of teaching, social, and cognitive presence indicators in a community of inquiry

Wanstreet, Constance Elizabeth 08 March 2007 (has links)
No description available.
350

Factors to Consider for Implementing Blended Learning in Saudi Higher Education Institutions: An Integrative Literature Review

Alsobhi, Rania Masoud M. 22 June 2021 (has links)
Blended/hybrid learning, a combination of face to face and online learning to deliver instruction, is growing in popularity at institutions of higher education, and may lead to many benefits for students, faculty, and administrators. However, the implementation of blended learning (BL) is a complex process. Although the move towards BL adoption is generally accepted by faculty, questions still remain when it comes to adopting and implementing standards across institutions. Given this problem, this integrative literature review was conducted to identify possible factors that impact the process of implementing BL smoothly and successfully at higher education institutions. The purpose of this study was to identify related institutional factors from empirical studies published from 2000 to 2020. Findings from this study may offer institutions a guide to effectively create, execute, and assess BL programs and courses. The study provides recommendations that may be impactful for decision-makers at Saudi higher education institutions. / Doctor of Philosophy / Blended/hybrid learning, a combination of face to face and online learning to deliver instruction, has become popular at universities because it provides advantages for students, faculty members, and the university itself. However, the implementation of blended learning (BL) is a challenging process, and in many instances there is not enough guidance available to assist universities through the process. For this reason, this study has been conducted with the goal of identifying possible factors relating to implementing BL smoothly and successfully at universities. Findings from this study may offer institutions a guide to effectively create, execute, and assess BL programs and courses. The study provides recommendations that may be impactful for decision-makers at Saudi universities

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