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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.
61

Improving Breastfeeding Outcomes: A Pilot Randomized Controlled Trial of a Self-efficacy Intervention with Primiparous Mothers

McQueen, Karen A. 13 April 2010 (has links)
Breastfeeding is recommended as the optimal source of nutrition for newborns for the first 6 months of life and beyond with the addition of complementary foods. While breastfeeding initiation rates have been increasing, duration rates remain a concern as many women prematurely discontinue due to difficulties encountered rather than maternal choice. In addition, there is a sizable gap between rates of exclusive breastfeeding and current recommendations. Targeting modifiable variables that may be amenable to intervention is one strategy to improve breastfeeding outcomes. One such modifiable variable is breastfeeding self-efficacy. Although research has clearly shown that breastfeeding self-efficacy is predictive of breastfeeding duration and exclusivity, it is unknown whether it can be enhanced to improve breastfeeding outcomes. The purpose of this pilot randomized controlled trial was to examine the feasibility and compliance of a newly developed trial protocol and the acceptability of an intervention to increase breastfeeding self-efficacy in the immediate postpartum period. Secondary outcomes included determining whether there were any trends between groups related to breastfeeding self-efficacy, duration, and exclusivity. Participants included 150 primiparous mothers who were breastfeeding their healthy, full-term infants. Eligible and consenting mothers were randomized to either a control group (standard postpartum care) or an intervention group (standard postpartum care plus the self-efficacy intervention). Participants allocated to the intervention group received three individualized, self-efficacy enhancing sessions with the researcher; two sessions were conducted in hospital, and one was administered via telephone 1 week following hospital discharge. A research assistant blinded to group allocation collected outcome data at 4 and 8 weeks postpartum. The results suggested that the administration of the intervention was feasible and that there was a high degree of protocol compliance; the majority of participants reported that the intervention was beneficial. Secondary outcomes identified that there was a trend among participants in the intervention group to have improved breastfeeding outcomes, including higher rates of breastfeeding self-efficacy, duration, and exclusivity at 4 and 8 weeks postpartum. Preliminary evidence also suggested that the self-efficacy intervention may have assisted to decrease perceptions of insufficient milk supply among the intervention group participants. Overall, the findings from this pilot trial indicated that a larger trial is warranted.
62

Samarbete och kamratskap på fritidshem

Pettersson, Hanna January 2019 (has links)
Utvecklingsarbetet har i syfte att eleverna ska träna på att samarbeta för att stärka kamratskap på fritidshemmet. På det fritidshemmet där utvecklingsarbetet genomfördes på vänder sig till årskurs 2. Utgångspunkten för arbetet var att eleverna skulle träna på att samarbeta med varandra och genom detta få bättre kamratskap. Utvecklingsarbetet ska vara en pilot för ett arbete som kan bli ett kvalitetsarbete som kan fortgå på ett fritidshem. Under sex veckor genomfördes övningar som var planerade och under övningarna dokumenterades det genom observation och processdagbok. I arbetet ingick även barnsamtal i efterarbetet. Övningarna som genomfördes planerades av mig med samråd av lärarna på fritidshemmet. I nulägesanalysen framgick det att det hade varit mycket missförstånd mellan eleverna på fritidshemmet och därför skulle det behövas vara ett arbete kring eleverna om samarbete och kamratskap. I reflektionen visar hur utvecklingsarbetet föll ut.
63

ASSESSING AND IMPROVING INTER-RATER AND REFERENT-RATER AGREEMENT OF PILOT PERFORMANCE EVALUATION

Allen Xie (5930417) 17 December 2018 (has links)
The Federal Aviation Administration (FAA) has been promoting Advanced Qualification Program (AQP) for pilot training and checking at Federal Aviation Regulations (FAR) Part 121 and Part 135 air carriers. Regarding pilot performance evaluation, instructors and evaluators assign scores to a student based on specific grading standards. To ensure the best possible quality of training and the highest level of safety, it is vital for different instructors and evaluators to grade students based on the same standard. Therefore, inter-rater and referent-rater agreement are paramount in calibrating the performance evaluation among different instructors and evaluators. This study was designed to test whether a focused workshop could increase the level of inter-rater and referent-rater agreement. A pre-test post-test control group experiment was conducted on a total of 29 Certified Flight Instructors (CFIs) at Purdue University. Participants were asked to watch several pre-scripted video flight scenarios recorded in an Embraer Phenom 100 FTD and give grades to the student pilots in the videos. After a rater training workshop that consisted of Behavior-Observation Training, Performance-Dimension Training, and Frame-of-Reference Training, participants in the treatment group were able to achieve a significantly higher level of inter-rater and referent-rater agreement.
64

Performance enhancement of massive MIMO systems under channel correlation and pilot contamination

Alkhaled, Makram Hashim Mahmood January 2018 (has links)
The past decade has seen an enormous increase in the number of connected wireless devices, and currently there are billions of devices that are connected and managed by wireless networks. At the same time, the applications that are running on these devices have also developed significantly and became more data rate insatiable. As the number of wireless devices and the demand for a high data rate will always increase, in addition to the growing concern about the energy consumption of wireless communication systems, the future wireless communication systems will have to meet three main requirements. These three requirements are: i) being able to achieve high throughput; ii) serving a large number of users simultaneously; and iii) being energy efficient (less energy consumption). Massive multiple-input multiple-output (MIMO) technology can satisfy the aforementioned requirements; and thus, it is a promising candidate technology for the next generations of wireless communication systems. Massive MIMO technology simply refers to the idea of utilizing a large number of antennas at the base station (BS) to serve a large number of users simultaneously using the same time-frequency resources. The hypothesis behind using a massive number of antennas at the BS is that as the number of antennas increases, the channels become favourable. In other words, the channel vectors between the users and their serving BS become (nearly) pairwisely orthogonal as the number of BS antennas increases. This in turn enables the use of linear processing at the BS to achieve near optimal performance. Moreover, a huge throughput and energy efficiency can be attained due to users multiplexing and array gain. In this thesis, we investigate the performance of massive MIMO systems under different scenarios. Firstly, we investigate the performance of a single-cell multi-user massive MIMO system, in which the channel vectors for the different users are assumed to be correlated. In this aspect, we propose two algorithms for users grouping that aim to improve the system performance. Afterwards, the problem of pilot contamination in multi-cell massive MIMO systems is discussed. Based on this discussion, we propose a pilot allocation algorithm that maximizes the minimum achievable rate in a target cell. Following that, we consider two different scenarios for pilot sequences allocation in multi-cell massive MIMO systems. Lower bounds on the achievable rates are derived for two linear detectors, and the performance under different system settings is analysed and discussed for both scenarios. Finally, two algorithms for pilot sequences allocation are proposed. The first algorithm takes advantage of the multiplicity of pilot sequences over the number of users to improve the achievable rate of edge cell users. While the second algorithm aims to mitigate the negative impact of pilot contamination by utilizing more system resources for the channel estimation process to reduce the inter-cell interference.
65

The Relationship Between Nicotine Withdrawal Symptoms and Nicotine Habits in Pilots

January 2019 (has links)
abstract: Nicotine and tobacco use, whether it be through cigarette smoking or other devices, creates negative health conditions in pilots. The literature that was reviewed pertained to nicotine withdrawal symptoms and their negative impact on pilot performance. There have been studies conducted in order to explore how these symptoms impact pilot performance using cigarettes as the only nicotine device and does not specify the nicotine levels or the frequency of use. This thesis extends this work to examine the relationship between the nicotine withdrawal symptoms and the nicotine behaviors of pilots. It was hypothesized that the extent of withdrawal symptoms may differ by device and by nicotine levels and frequency of use, with higher levels and more frequent use being associated with more severe withdrawal symptoms. These behaviors included the device they use to take nicotine whether it be cigarettes, vaporizers, e-cigarettes, or smokeless tobacco. The behaviors also included exploration of how nicotine levels relate to withdrawal symptoms whether the nicotine level is as low as 3mg or high as 36mg. The last relationship that was explored was that between the withdrawal symptoms presented in pilots and how often they used nicotine, whether it be often as every day or less frequent as 1-2 times a year. It was found that there is no statistical relationship between nicotine withdrawal symptoms and the nicotine habits such as device used, nicotine level used, and frequency of use. / Dissertation/Thesis / Masters Thesis Engineering 2019
66

Exposure assessment of traffic-related pm10 pollution in outdoor play areas of early childhood centres

Lyne, Mark January 2008 (has links)
This thesis seeks to assess the exposure of children in outdoor play areas of early childhood centres in Auckland City to traffic-related PM10 pollution. An estimated 400 premature deaths occur each year in New Zealand due to motor vehicle emissions. In addition to premature deaths, acute and chronic health effects including asthma, chronic obstructive pulmonary disease (COPD), heart disease and bronchitis, as well as increased hospitalisations and restricted activity days (sick days) are also associated with vehicle emissions. Epidemiological studies have shown that respiratory diseases such as asthma can be exacerbated by increases in the concentration of particulates of less than 10 microns in diameter (PM10) from motor vehicle emissions. Significant positive associations have been found between proximity to heavily travelled roads and increased childhood respiratory disease symptoms including hospitalisations for childhood asthma. In spite of this evidence, many early childhood centres in Auckland are located adjacent to busy roads. Children at these early childhood centres spend much of their time playing in the outdoor areas of these centres with the potential for particulates from motor vehicle emissions to exacerbate symptoms in those children already suffering from respiratory disease and asthma. Very little research has been carried out either in New Zealand or internationally on the air quality of outdoor play areas of early childhood centres in relation to motor vehicle emissions and childhood respiratory disease and asthma. The extent of monitoring is also limited and the amount of exposure data available in New Zealand relatively sparse, particularly in comparison with Europe. Levels of traffic-related PM10 in the outdoor play areas of early childhood centres were measured in centres located adjacent to busy roads and in centres away from a quiet road or adjacent to a very quiet road for comparison. Two of five early childhood centres located alongside busy roads had PM10 levels that exceeded the World Health Organization (WHO) guideline value. While PM10 levels monitored at the other three centres located alongside busy roads did not exceed the WHO guideline value, results were often only marginally within this guideline value. In contrast, PM10 levels monitored at two centres located away from a quiet road and one centre located adjacent to a very quiet road were well within the WHO guideline value. This pilot study provides preliminary evidence that children attending early childhood centres located alongside busy roads have greater exposure to traffic-related PM10 pollution than those attending early childhood centres located away from a quiet road or adjacent to a very quiet road. If the link between PM10 exposure and health effects is causal, as suggested by epidemiological studies, then children attending early childhood centres proximal to busy roads are at a greater risk of respiratory illness than children attending early childhood centres adjacent to quiet roads. Further work is required to confirm the findings in this small sample of air quality around early childhood centres in a larger sample, and possibly to undertake an epidemiological study to confirm the link to health effects. Drawing on the precautionary principle, prudent territorial local authorities should be encouraged to introduce regulations ensuring that any new early childhood centres are located at a specified distance from major roads, and that information for parents, ongoing PM10 monitoring and processes for issuing PM10 advisories when limits are exceeded are available in existing early childhood centres that are adjacent to busy roads.
67

Assembly of a UAV : hardware design of a UAV

BOZKURT, Ugur, Aslan, Mustafa January 2009 (has links)
<p><em>This bachelor thesis is dedicated to assemble the hardware system of a UAV (Unmanned Aerial Vehicle) in order to prepare the platform for an autonomous flight in the air for a given path through the pre-programmed check points. A UAV is an aircraft that contains sensors, GPS, radio system, servomechanisms and computers, which provide the capability of an autonomous flight without a human pilot in the cockpit. A stable flight requires sensing the roll, pitch, and yaw angles of aircraft. Roll and pitch angles were ensured by a sensor system of FMA Direct Company called co-pilot flight stabilization system (CPD4), which allows controlling ailerons and elevator manually.</em></p><p><em>An autopilot is required for steering the aircraft autonomously according the GPS data and the establish waypoints that the airplane have to pass by. The GPS gives heading information to the autopilot, and this uses the information of the next waypoint to decide which direction to go. Hereby an autonomous flight is provided. In this project a lego mindstorm NXT was used as an autopilot that is product of LEGO Company [1]. The output of the autopilot is used to control the airplane servos to fly in the desired direction. A software and hardware interface was designed to allow the autopilot to receive the data from the co-pilot sensor and to transmit data to the co-pilot processor, which will finally steer the actuator servos. Experiments were performed with different parts of the system and the results reported.</em></p>
68

The role of community-driven participatory monitoring and evaluation in empowering communities and improving their decision making: a case study of the KARI/CIAT collaborative project, Coastal Kenya.

Sangole, Noel. January 2007 (has links)
<p>The researcher has been working for CIAT, as a community development facilitator and research assistant for past five years (2001-2006). CIAT has been involved in testing tools and methods for promoting participation and tracking changes at community level under different pilot projects in Eastern and Central Africa in partnership with national research organizations of respective countries. One of CIAT&rsquo / s areas of research is developing participatory monitoring and evaluation systems that are appropriate for rural communities. The researcher has been involved in designing and setting up community-driven participatory monitoring and evaluation systems on a pilot basis with communities in Eastern and Southern Africa.</p>
69

Methods for Validatng Cockpit Design The best tool for the task

Singer, Gideon January 2002 (has links)
No description available.
70

An adaptive pitch axis autopilot design for an unstable nonminimum phase pitch axis model

Chen, Long Ren 14 June 1990 (has links)
An adaptive pitch axis autopilot design procedure is presented. The design procedure is applicable to both stable and unstable pitch axis models and to those having nonminimum phase. The design approach assumes the adaptive autopilot is activated after achieving level flight. It is shown a rate-feedback compensator can be designed to ensure stable level flight pitch axis operation for the entire desired flight regime. The adaptive control loop design utilizes a pole-placement algorithm. The closed-loop characteristic polynomial is designed to have dominant poles of that of an ideal second order system to obtain the desired transient response. The identification of the system uses a modified least-squares algorithm with a variable forgetting factor. The nonlinear pitch axis model is used in simulations to evaluate the design. Command response tests include the step response and the ramp command response. Simulation results indicate that the adaptive pitch axis autopilot is capable of tracking altitude commands after activation. The closed-loop system response is close to that of the ideal second order system having the dominant poles. / Graduation date: 1991

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