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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.
91

Multipath Mitigation for Aeronautical Telemetry with Multiple Antennas

Williams, Ian E. 10 1900 (has links)
ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Frequency selective multipath is a key performance limiter for aeronautical telemetry applications. Our research explores multipath mitigation techniques with ARTM Tier-1 waveforms using linear adaptive filters, multiple receive antennas and error-based best source selection. Single antenna adaptive equalization alone is unable to substantially improve performance under certain channel conditions. Analytical investigations demonstrate that nonlinear channel phase response is the principal cause of performance loss. In this adverse environment, spatial diversity with multiple receive antennas along with error-based best source selection are capable of improving bit error rate performance by 5dB for each additional antenna.
92

ENHANCING THE PCM/FM LINK - WITHOUT THE MATH

Fewer, Colm, Wilmot, Sinbad 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Since the 1970s PCM/FM has been the dominant modulation scheme used for RF telemetry. However more stringent spectrum availability as well as increasing data rates means that more advanced transmission methods are required to keep pace with industry demands. ARTM Tier-I and Tier-II are examples of how the PCM/FM link can be enhanced. However these techniques require a significant increase in the complexity of the receiver/detector for optimal recovery. This paper focuses on a quantitative approach to improving the rate and quality of data using existing PCM/FM links. In particular ACRA CONTROL and BAE SYSTEMS set themselves the goal of revisiting the pre-modulation filter, diversity combiner and bit-sync. By implementing programmable adaptive hardware, it was possible to explore the various tradeoffs offered by modifying pulse shapes and spectral occupancy, inclusion of forward error correction and smart source selection. This papers looks at the improvements achieved at each phase of the evaluation.
93

UTTR BEST TELEMETRY SOURCE SELECTOR

Rigley, Kenneth H., Wheelwright, David H., Fowers, Brandt H. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / The UTTR (Utah Test & Training Range) offers the largest over land test and training airspace in the continental United States. It provides excellent telemetry data processing capability through a number of TM (telemetry) sites. Selecting the best source of telemetry data for optimum coverage from these many sites can be very involved and challenging for ground station personnel. Computer-based best source selection automates this process, thereby increasing accuracy and efficiency. This paper discusses the capabilities of the BTSS (Best Telemetry Source Selector), its background, design and development, applications, and future at the UTTR.
94

PC-Based Frame Optimizer Using Multiple PCM Files

Koh, Kwang-Ryul, Lee, Sang-Bum, Yi, Taek-Joon, Kim, Whan-Woo 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / Many engineers have tried to detect and correct erroneous data in telemetry communications. The best source selector can be used to combine data from two or more bit synchronizers to reduce frame error rates. An error-correcting code can be used as well. These techniques are absolutely helpful to obtain reliable telemetry data. However, some errors still remain and must be removed. This paper introduces the way to effectively merge multiple PCM files that are saved in different receiving sites, and shows nearly errorless data resulting from merging flight test data using a PC-based frame optimizer, which is a developed program.
95

Improvements in ranked set sampling

Haq, Abdul January 2014 (has links)
The main focus of many agricultural, ecological and environmental studies is to develop well designed, cost-effective and efficient sampling designs. Ranked set sampling (RSS) is one of those sampling methods that can help accomplish such objectives by incorporating prior information and expert knowledge to the design. In this thesis, new RSS schemes are suggested for efficiently estimating the population mean. These sampling schemes can be used as cost-effective alternatives to the traditional simple random sampling (SRS) and RSS schemes. It is shown that the mean estimators under the proposed sampling schemes are at least as efficient as the mean estimator with SRS. We consider the best linear unbiased estimators (BLUEs) and the best linear invariant estimators (BLIEs) for the unknown parameters (location and scale) of a location-scale family of distributions under double RSS (DRSS) scheme. The BLUEs and BLIEs with DRSS are more precise than their counterparts based on SRS and RSS schemes. We also consider the BLUEs based on DRSS and ordered DRSS (ODRSS) schemes for the unknown parameters of a simple linear regression model using replicated observations. It turns out that, in terms of relative efficiencies, the BLUEs under ODRSS are better than the BLUEs with SRS, RSS, ordered RSS (ORSS) and DRSS schemes. Quality control charts are widely recognized for their potential to be a powerful process monitoring tool of the statistical process control. These control charts are frequently used in many industrial and service organizations to monitor in-control and out-of-control performances of a production or manufacturing process. The RSS schemes have had considerable attention in the construction of quality control charts. We propose new exponentially weighted moving average (EWMA) control charts for monitoring the process mean and the process dispersion based on the BLUEs obtained under ORSS and ODRSS schemes. We also suggest an improved maximum EWMA control chart for simultaneously monitoring the process mean and dispersion based on the BLUEs with ORSS scheme. The proposed EWMA control charts perform substantially better than their counterparts based on SRS and RSS schemes. Finally, some new EWMA charts are also suggested for monitoring the process dispersion using the best linear unbiased absolute estimators of the scale parameter under SRS and RSS schemes.
96

Toward the Identification of a Body of Classic or Seminal Works in Adult Education: a Citation Analysis

Newcomer, Jane E. (Jane Elisabeth) 12 1900 (has links)
This bibliometric study examined 19,385 citations in the bibliographies, book reviews, and reading lists of 70 volumes of Adult Education Quarterly, Adult Education, Adult Education Bulletin, Adult Education Journal, and Journal of Adult Education, and 13 volumes of the Handbook of Adult Education in the United States to identify books published before 1960 which have been frequently cited before and after 1960. Through citation analysis, an initial list of 434 titles was reduced to a core list of 64 books cited five times or more during the years between 1934 and 1988. For the purposes of this study, numbers of citations were taken to mean importance of works by indicating usefulness to subsequent authors. Of the 64 books, 55 had received at least one citation before 1960 and 57 had received at least one citation after 1960. While not all 64 of the core works constitute what might be called "classic works," it is suggested that classic works are likely to be found within the listed works.
97

Farmer Adoption of Best Management Practices Using Incentivized Conservation Programs

Miller, Jennifer Christine 01 January 2014 (has links)
Many farms in the United States impose negative externalities on society. Population growth and the accompanying increase in demand for food further promote this trend of environmental degradation as a by-product of food production. The USDA's Environmental Quality Incentives Program (EQIP) provides financial assistance to farmers who wish to address natural resource concerns by making structural improvements or implementing best management practices (BMPs) on their farms. Regional examinations of program implementation and incentive levels are needed to evaluate the effectiveness of EQIP at both the farm and environmental level. This research addresses this need in the following two ways. First, conjoint analysis was used to calculate the willingness to accept incentive levels desired by Vermont farmers for implementing three common BMPs and the relative importance of each attribute in their adoption decisions. Next, a survey was conducted to document Vermont farmers' experiences, or choices not to engage, with EQIP. The results of the conjoint analysis indicated that farmers' adoption decisions are most heavily influenced by the available implementation incentives and that the higher the incentive level offered, the more willing farmers are to adopt a practice. The survey results triangulated these findings as cost was the most frequently cited challenge farmers face when implementing BMPs and one third of respondents felt the cost-share amount they had received was inadequate. Although 46% of respondents reported receiving nonmonetary benefits, 43% had encountered challenges when enrolling or participating in EQIP. In addition, though contracts are designed to address specific resource concerns, 30% of respondents had not fully fixed the original issues with their contracts. This also indicates that the incentive levels offered in EQIP contracts may be lower than Vermont farmers' preferred incentive levels, affecting the adoption rate of BMPs and subsequently the environmental health and long term sustainability of Vermont's agricultural systems. Program areas ripe for improvement, key points for farmers weighing the costs and benefits of program participation, and future research opportunities are discussed in order to guide efforts to improve the effectiveness of EQIP in Vermont. This research also raises awareness of how much it costs to simultaneously support environmental health and food production in our current food system and who ultimately should bear this financial burden.
98

Employing "Best Practices" In Teacher Education: Faculty Perceptions Of Their Success And Their Needs In Preparing Teachers To Increase Student Achievement

Timsina, Prem P. 01 January 2014 (has links)
This qualitative study focuses on the faculty engaged in the preparation of secondary teachers at North East University (NEU). It seeks to discover how they see themselves as professionals and assess their work preparing future teachers in "Best Practices" of teaching so that they can effectively teach all students, particularly low achievers. To achieve the goal of this study, I conducted semi-structured individual interviews with those faculty who are engaged in preparing teachers at the secondary program. Eight participants were interviewed for this study, among them six participants were fully engaged in the teacher preparation. Once I collected the data from the interviews, then I transcribed, coded, analyzed the data, and identified similarities, differences, patterns, and themes from the interviews. The findings of this study indicate that these faculty have a strong commitment to preparing outstanding teachers that is rooted in their belief in social justice and equality. They expressed they have dreams about their teaching, about their student-teachers and about their program. The faculty are highly confident of their ability to educate secondary teachers and believe that they make a difference in the academic performance of those children their graduates serve in the schools. This study also concluded that the teacher educators at NEU's secondary program think they are successful in introducing "Best Practices" of teaching, especially helping their student-teachers in differentiating instructions, dealing with disabilities, teaching ELL students, employing technology in teaching, understanding diversity, culture and traditions, and preparing their student-teachers in examining issues relating to prejudice, discrimination, stereotyping, race, poverty, gender, social class and ethnicity.
99

Developing connections + Junction City, Kansas / Developing connections and Junction City, Kansas / Developing connections plus Junction City, Kansas

Rolfs, Brett T. January 1900 (has links)
Master of Landscape Architecture / Department of Landscape Architecture/Regional and Community Planning / William P. Winslow III / This project is of a personal interest to me, because Junction City, Kansas has been my home town since birth. The city is a rapidly growing community with a strong military presence from nearby Fort Riley, Kansas. The project will explore the capacity for effective growth while preventing the degradation of fragile natural resources within the community. It will also provide new amenities for the people of Junction City as well as capitalize on the existing natural amenities. The project provides storm water management solutions for an existing retail development and a proposed mixed use development incorporating sustainable practices. Studying the history and progressive nature of Junction City provides an understanding of how to embrace the design within the surrounding landscape. A model for responsible mixed use retail and residential development in Junction City is provided through this project. Storm water best management strategies were also implemented to improve the oxbow wetlands by capturing the first flush storm event as well as a 25 year storm event. Finally, the project should continue to shape the history and enthusiasm of Junction City and its people.
100

Assisterad befruktning för ensamstående kvinnor - Barnets bästa eller en vuxens intresse att bli förälder? / Assisted reproduction for single women - The child´s best interests or the adult´s interest to become a parent?

Kotka, Louise January 2017 (has links)
No description available.

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