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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.
271

DATA COMPRESSION STATISTICS AND IMPLICATIONS

Horan, Sheila 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Bandwidth is a precious commodity. In order to make the best use of what is available, better modulation schemes need to be developed, or less data needs to be sent. This paper will investigate the option of sending less data via data compression. The structure and the entropy of the data determine how much lossless compression can be obtained for a given set of data. This paper shows the data structure and entropy for several actual telemetry data sets and the resulting lossless compression obtainable using data compression techniques.
272

Energetic study of a residential building in Skutskär and savings proposal

Masip-Sanchis, Ximo January 2016 (has links)
This project consists on the Energy audit carried out on a residential building in Skutskär, property of the company Älvkarlebyhus, which is placed in the Älvkarleby municipality, belonging to Uppsala County in Sweden. The aim of the Energy audit is to obtain how much Energy is used, when is it used and how is it used. As well as the costs of the Energy use. The aim of the Energy audit also consists in reduces the Energy use applying efficiency measures. The audit carried out consist on identifying the heat losses and heat gains of the building, thus establishing an Energy balance that will reflect the Energy state of the building and finally propose some efficiency measures that could be applied. With this purpose, a strong method was developed in order to obtain as accurate results as possible. This method studies separately each component of the balance in order to get a better approach. The idea when working and present the results is to manage all the information in an easy way and present it in an easily understandable way for everyone, thus was used a spreadsheet. The expected results have been achieved; the difference between the heat losses and gains is of 0 MWh, which represents the balance 0 and all the values obtained are according to the experience values, which achieve the expected results. The total heat gain of the balance accounts for 1575,23 MWh. It is compounded by the District heating consumption which accounts 742,22 MWh that represents the 47 % of the heat gain and by the free heating which accounts for 832,79 MWh that represents the 53 %. The free heating is compounded by solar radiation which accounts for 643,36 MWh representing 41 % and for Internal heating which accounts for 189,43 MWh that represents 12 %. The total heat loss of the balance accounts for 1575,23 MWh. It is compounded by transmission losses which accounts for 875,46 MWh that represents 56 %, mechanical ventilation which accounts for 369,89 MWh that represents the 23 %, natural ventilation which account for 182,88 MWh that represents 12 % and hot tap water which account for 147 and represents 9 %. The efficiency measures will improve the Energy use in the buildings; especially in the cases were the Energy usage is too high, as in the case of transmission losses. Thus, the efficiency measures will be proposed mainly to alleviate the high values but also to improve other inefficient uses of the Energy. There are some efficiency measures proposed for every component of the balance and there is also some recommendation for the company in order to implement the most attractive ones, taking into account its profitability. These measures are only proposed and not studied deeply because of the main limitation of this thesis. Therefore, it is recommended to continue the study in order to examine and analyse deeply each measure, according to the energetic survey already done.
273

The effect of water-use efficiency on catchment runoff in Great Britain

Williams, Jamie January 2014 (has links)
No description available.
274

Is 'Not-Trading' Informative? Evidence from Corporate Insiders' Portfolios

DeVault, Luke January 2016 (has links)
Some corporate insiders hold insider equity holdings in multiple companies (portfolio insiders). I hypothesize that information can be garnered not only from their trades (e.g., an insider sale of firm A on day t), but from their not-traded securities (e.g. the insider's decision not to sell firms B and C on day t). Specifically, an insider's decision not to sell (purchase) security B at the time of the sale (purchase) of security A, is a positive (negative) signal for security B, the not-sold (not-bought) security. The paper presents three major empirical findings. First, portfolio insider not-sold securities following a sale earn large risk-adjusted returns outperforming the not-purchased securities following a purchase. Second, portfolio insiders' purchases are more informative than single-firm insiders' purchases. Finally, the results suggest that abnormal returns associated with insider purchases result from markets reacting to the revelation of the insider purchase while abnormal returns associated with not-sold securities appear to result from insiders delaying sales prior to positive firm-specific events.
275

Wireless Transducer Systems Architectures – A User’s Perspective

Blakely, Patrick A. 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper provides essential requirements and describes some possible architectures of so-called Wireless Transducers Systems from the user’s perspective and discusses the application advantages of each architecture, in the airplane-testing environment. The intent of this paper is to stimulate discussion in the transducer user and supplier communities and standards committees, leading to increased product suitability and lower cost for commercial off the shelf wireless transducer products.
276

THE S-BAND COAXIAL WAVEGUIDE TRACKING FEED FOR ARIA

Mahon, John P. 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / This paper contains a description of a new technology tracking feed and a discussion of the features which make this feed unique and allow it to perform better than any other comparable feed. Also included in this report are measured primary antenna patterns, measured and estimated phase tracking performance and estimated aperture efficiency. The latter two items were calculated by integrating the measured primary patterns.
277

DESCRIPTION AND PERFORMANCE RESULTS FOR THE ADVANCED RANGE TELEMETRY (ARTM) TIER II WAVEFORM

Geoghegan, Mark 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / The Advanced Range Telemetry (ARTM) program is a tri-service telemetry modernization project whose goal is to assure that all Department of Defense (DoD) test and training ranges are able to use telemetry as necessary to carry out their respective missions. Multi-h Continuous Phase Modulation (CPM) has been selected by the ARTM JPO as the Tier II ARTM waveform, because it offers significant improvements over both legacy telemetry waveforms (PCM/FM) and the newly-introduced Tier I waveform (Feher-patented FQPSK) in terms of spectral containment and detection efficiency, while retaining a constant envelope characteristic. The paper describes the theoretical and measured performance of the ARTM Tier II multi-h CPM waveform, and the implementation of the trellis demodulator being developed for it.
278

Exploring the relationships between influencing factors and performance for construction joint ventures

Chen, Hua, 陳華 January 2006 (has links)
published_or_final_version / abstract / Real Estate and Construction / Doctoral / Doctor of Philosophy
279

Formability and hydroforming of anisotropic aluminum tubes

Korkolis, Ioannis 19 October 2009 (has links)
The automotive industry is required to meet improved fuel efficiency standards and stricter emission controls. Aluminum tube hydroforming is particularly well suited in meeting the goals of lighter, more fuel-efficient and less polluting cars. Its wider use in industry is hindered however by the reduced ductility and more complex constitutive behavior of aluminum in comparison to the steels that it is meant to replace. This study aims to address these issues by improving the understanding of the limitations of the process as applied to aluminum alloys. A series of hydroforming experiments were conducted in a custom testing facility, designed and constructed for the purposes of this project. At the same time, several levels of modeling of the process, of increasing complexity, were developed. A comparison of these models to the experiments revealed a serious deficiency in predicting burst, which was found experimentally to be one of the main limiting factors of the process. This discrepancy between theory and experiment was linked to the adoption of the von Mises yield function for the material at hand. This prompted a separate study, combining experiments and analysis, to calibrate alternative, non-quadratic anisotropic yield functions and assess their performance in predicting burst. The experiments involved testing tubes under combined internal pressure and axial load to failure using various proportional and non-proportional loading paths (free inflation). A number of state of the art yield functions were then implemented in numerical models of these experiments and calibrated to reproduce the induced strain paths and failure strains. The constitutive models were subsequently employed in the finite element models of the hydroforming experiments. The results demonstrate that localized wall thinning in the presence of contact, as it occurs in hydroforming as well as other sheet metal forming problems, is a fully 3D process requiring appropriate modeling with solid elements. This success also required the use of non-quadratic yield functions in the constitutive modeling, although the anisotropy present did not play as profound a role as it did in the simulation of the free inflation experiments. In addition, corresponding shell element calculations were deficient in capturing this type of localization that precipitates failure, irrespective of the sophistication of the constitutive model adopted. This finding contradicts current practice in modeling of sheet metal forming, where the thin-walled assumption is customarily adopted. / text
280

Refining building energy modeling through aggregate analysis and probabilistic methods associated with occupant presence

Stoppel, Christopher Michael 23 October 2014 (has links)
The building sector represents the largest energy consumer among the United States' end use sectors. As a result, the public and private sector will continue to place great emphasis on designing energy efficient buildings that minimize operating costs while maintaining a healthy environment for its occupants. Creating design-phase building energy models can facilitate the process of selecting life-cycle appropriate design strategies aimed at maximizing building energy efficiency. The primary objective of this research study is to gain greater insight into likely causes of variation between energy predictions derived from building energy models and building energy performance during post-occupancy. Identifying sources of error can be used to improve future modeling efforts that can potentially lead to greater accuracy and better decisions made during the building's design phase. My research approach is to develop a method for conducting retrospective analysis of building energy models in the areas that affect the building's predicted and actual energy consumption. This entails collecting pre-construction and post-occupancy related data from various entities that exhibit influence on the building's energy performance. The method is then applied to recently-constructed military dormitory buildings that utilized building energy modeling and now have actual, metered building energy consumption data. The study also examines how building occupancy impacts energy performance. The value of this work will provide additional insight to future building energy modeling efforts. / text

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