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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.
261

A novel platform incorporating multiple forms of communication to support applications in a mobile environment

Elton, James January 2014 (has links)
This thesis discusses the creation of a novel platform that incorporates multiple communication methods, including SMS, email and web-based technologies, for interacting with users of mobile communication devices. The platform utilises people in a mobile environment to solve a range of different application problems, where each problem is a separate and distinct scenario type with unique objectives. There are existing applications available that interact with users of mobile communication devices to provide a service, such as regular weather updates to the users. Other applications have been designed to manage and coordinate the users to perform tasks within a mobile environment, such as performing field studies for scientific purposes. However, the existing applications are designed for only one specific scenario, with the design and implementation solely focused on solving the objectives of that scenario. Each component of these applications needs to be developed from scratch in order to cater for the application s requirements. There is currently no integrated communications platform that offers a framework for supporting a range of different scenario types. The new platform, entitled the Connected-Mobile Platform, aims to support the rapid development and implementation of new scenarios. This platform is composed of a framework of generic components that enable the active running of multiple scenarios concurrently, with the ability to tailor to the requirements of new scenarios as they arise via a structured process. The platform facilitates a means to coordinate its users in order to tackle the objectives of a scenario. The thesis investigates several system architectures to determine an appropriate architectural design for constructing the proposed platform. The platform has a generic framework, based on a client-server architecture, to facilitate the inclusion of a multitude of scenarios. A scenario represents a problem or an event, whereby the platform can utilise and interact with users of mobile communication devices to attempt to solve the objectives of the scenario. Three mobile communication methods are supported; the Short Message Service, electronic mail and web-forms via the mobile internet. Users are able to select and switch between the different methods. The thesis describes the platform s tailored communication structure for scenarios and autonomous analysis of messages. The thesis discusses case studies of two different scenarios to evaluate the platform s facilities for rapid scenario development. The Diet Diary scenario, which is for individual users, aims to manage a user s daily calorie intake to help them reach their desired weight goal. The focus is on the platform s functionality for analysing and responding to messages autonomously. The Missing Persons scenario, which utilises multiple users, involves tracking and locating people who have been reported missing. The focus is on the platform s functionality for coordinating the multiple users, through the creation of assignments, in order to distribute the scenario objectives. The thesis concludes by highlighting the novel features of the platform and identifying opportunities for future work.
262

Galactic microlensing : binary-lens light curve morphologies and results from the Rosetta spacecraft bulge survey

Liebig, Christine Elisabeth January 2014 (has links)
For 20 years now, gravitational microlensing observations towards the Galactic bulge have provided us with a wealth of information about the stellar and planetary content of our Galaxy, which is inaccessible via other current methods. This thesis summarises work on two research topics that arose in the context of exoplanetary microlensing, but we take a step back and consider ways of increasing our understanding of more fundamental phenomena: firstly, stellar microlenses in our Galaxy that were stereoscopically observed and, secondly, the morphological variety of binary-lens light curves. In autumn 2008, the ESA Rosetta spacecraft surveyed the Galactic bulge for microlensing events. With a baseline of ∼1.6 AU between the spacecraft and ground observations, significant parallax effects can be expected. We develop a photometry pipeline to deal with a severely undersampled point spread function in the crowded fields of the Galactic bulge, making use of complementary ground observations. Comparison of Rosetta and OGLE light curves provides the microlens parallax π[subscript{E}] , which constrains the mass and distance of the observed lenses. The lens mass could be fully determined if future proper motion measurements were obtained, whereas the lens distance additionally requires the determination of the source distance. In the second project, we present a detailed study of microlensing light curve morphologies. We provide a complete morphological classification for the case of the equal-mass binary lens, which makes use of the realisation that any microlensing peak can be categorised as one of only four types: cusp-grazing, cusp-crossing, fold-crossing or fold-grazing. As a means for this classification, we develop a caustic feature notation, which can be universally applied to binary lens caustics. Ultimately, this study aims to refine light curve modelling approaches by providing an optimal choice of initial parameter sets, while ensuring complete coverage of the relevant parameter space.
263

MULTIPROCESSOR-BASED DATA ACQUISITION AND ANALYSIS

Lynch, Thomas J., III, Fortmann, Thomas E., Briscoe, Howard, Fidell, Sanford 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1989 / Town & Country Hotel & Convention Center, San Diego, California / Multiprocessing computer systems offer several attractive advantages for telemetry-related data acquisition and processing applications. These include: (1) high-bandwidth, fail-soft operation with convenient, low-cost, growth paths, (2) cost-effective integration and clustering of data acquisition, decommutation, monitoring, archiving, analysis, and display processing, and (3) support for modern telemetry system architectures that allow concurrent network access to test data (for both real-time and post-test analyses) by multiple analysts. This paper asserts that today’s general-purpose hardware and software offer viable platforms for these applications. One such system, currently under development, closely couples VME data buses and other off-the-shelf components, parallel processing computers, and commercial data analysis packages to acquire, process, display, and analyze telemetry and other data from a major weapon system. This approach blurs the formerly clear architectural distinction in telemetry data processing systems between special-purpose, front-end, preprocessing hardware and generalpurpose, back-end, host computers used for further processing and display.
264

Measuring subhalo mass in redMaPPer clusters with CFHT Stripe 82 Survey

Li, Ran, Shan, Huanyuan, Kneib, Jean-Paul, Mo, Houjun, Rozo, Eduardo, Leauthaud, Alexie, Moustakas, John, Xie, Lizhi, Erben, Thomas, Van Waerbeke, Ludovic, Makler, Martin, Rykoff, Eli, Moraes, Bruno 21 May 2016 (has links)
We use the shear catalogue from the CFHT Stripe-82 Survey to measure the subhalo masses of satellite galaxies in redMaPPer clusters. Assuming a Chabrier initial mass function and a truncated NFW model for the subhalo mass distribution, we find that the subhalo mass to galaxy stellar mass ratio increases as a function of projected halo-centric radius r(p), from M-sub/M-star = 4.43(-2.23)(+6.63) at r(p) is an element of [0.1, 0.3] h(-1) Mpc toM(sub)/M-star = 75.40(-19.09)(+19.73) at r(p) is an element of [0.6, 0.9] h(-1) Mpc. We also investigate the dependence of subhalo masses on stellar mass by splitting satellite galaxies into two stellar mass bins: 10 < log (M-star/h(-1) M-circle dot) < 10.5 and 11 < log (M-star/h(-1) M-circle dot) < 12. The best-fitting subhalomass of the more massive satellite galaxy bin is larger than that of the lessmassive satellites: log(M-sub/h(-1) M-circle dot) = 11.14(-0.73)(+0.66) (M-sub/M-star = 19.5(-17.9)(+19.8)) versus log(M-sub/h(-1) M-circle dot) = 12.38(-0.16)(+0.16) (M-sub/M-star = 21.1(-7.7)(+7.4)).
265

Island biogeography of young land uplift islands - viewed through the lens of bryophytes in a northern Swedish archipelago / Öbiogeografi hos unga landhöjningsöar - betraktad ur ett mossperspektiv.

Karlsson Tiselius, Andreas January 2016 (has links)
Increasing habitat fragmentation and rapid global warming is changing the conditions for species populations and ecological communities around the world. This presents challenges for the maintenance of biodiversity and a dominant paradigm for conservation in fragmented habitats is given by island biogeography and metapopulation (or metacommunity) ecology. In this thesis I approach key concepts (area, connectivity and community assembly) in island biogeography and metacommunity ecology within the context of a dynamic land uplift archipelago. The presented work consists of two interwoven themes: (i) A methodological theme in which statistical approaches are developed to deal with the complexities of multispecies dynamic systems, and (ii) an applied theme dealing with community assembly and island biogeography of bryophytes on young land uplift islands. To describe island connectivity for entire species assemblages, an approach using functional principal component analysis (fPCA) on patch connectivity functions (the connectivity of an island as a continuous function of a variable representing the spatial scale of species dispersal capacities) was developed. In addition, a new statistical method, functional co-inertia analysis (fCoIA), for analyzing co-variation between multivariate species data and continuous functions was developed and applied to the relation between bryophyte species incidences and the island age/area-dynamics. Primarily asexual bryophyte species are dispersal limited and presence probabilities are related to island connectivity. No such patterns were found for species, at least occasionally, producing spores. Our results suggest that bryophyte dispersal is regulated by the contribution of spores to a regional spore rain and that bryophyte species with low spore output at the landscape level may be extra vulnerable under habitat fragmentation and loss. Having specialized asexual propagules increases the presence probabilities on islands, partly compensating for the dispersal limitation in asexual species. This suggests a trade-off between dispersal and establishment capacity, but also points to the importance of local dispersal for maintaining populations under the succession driven spatial turnover of microsites on the islands. Bryophyte colonization is strongly limited by habitat availability when a given habitats is rare, but there seems to exist a threshold over which other processes (e.g. dispersal limitation) become more important. Species with more vagile life history strategies appear to be stronger affected by the area of available habitats than many perennial species
266

TELEMETRY IN TESTING OF UNDERSEAS WEAPONS

Hull, Roy T., Jr. 11 1900 (has links)
International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The performance testing of underseas weapons involves many of the same challenges as for other “smart” systems. Data sets on the order of GigaBytes must be extracted, processed, analyzed, and stored. A few KiloBytes of significant information must be efficiently identified and accessed for analysis out of the great mass of data. Data from various sources must be time correlated and fused together to allow full analysis of the complex interactions which lead to a given test result. The fact that the various sources all use different formats and medias just adds to the fun. Testing of underseas weapons also involves some unique problems. Since real time data transmission is not practical; the vast bulk of the test data is recorded and then recovered with the vehicle at the end of the test. Acoustics are relied on for identification and ranging. As systems continue to get smarter; the rates, capacities, and “smarts” of the equipment and software used to process test data must similarly increase. The NUWES telemetry capabilities developed to test and analyze underseas weapons could be of use on other government related projects. “Key words: Telemetry, data processing, data analysis, undersea weapons, smart weapons, torpedoes, performance testing.”
267

A NEW 1553 ALL-BUS INSTRUMENTATION MONITOR

Berdugo, Albert, Ricker, William G. 11 1900 (has links)
International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Increased data throughput demands in military and avionics systems has led to the development of an advanced, All-Bus MIL-STD-1553 Instrumentation Monitor. This paper discusses an airborne unit which acquires the information from up to 8 dual-redundant buses, and formats the data for telemetry, recording or real-time analysis according to the requirements of IRIG-106-86, Chapter 8. The ALBUS-1553 acquires all or selected 1553 messages which are formatted into IRIG-compatible serial data stream outputs. Data is time tagged to microsecond resolution. The unit selectively transmits entire or partial 1553 messages under program control. This results in reduced transmission bandwidth if prior knowledge of 1553 traffic is known. The ALBUS also encodes analog voice inputs, discrete userword inputs and multiplexed analog (overhead) inputs. The unit is provided in a ruggedized airborne housing utilizing standard ATR packaging,
268

COMPUTER ANALYSIS OF THE OXFORD CONTINUOUS BLOOD PRESSURE MONITORING: DATA PROCESSING SYSTEM

Di Marco, A., Cordone, L., Palatini, P., Mormino, P., Pessina, A.C., Sperti, G., Dal Palú, C. 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 1984 / Riviera Hotel, Las Vegas, Nevada / Blood pressure signals recorded continuously in ambulatory patients using the Oxford system were analyzed by an IBM 370 computer in order to obtain beat by beat systolic and diastolic blood pressure along 24 hour blood pressure recordings. The method of digitizing the signal and the analysis of the sphygmogram are presented and discussed. Synthesis of the several thousands data obtained in 24 hour recordings and plotting of the data for clinical purposes and pharmacological studies are also reported.
269

Challenges Involved in the Automation of Regression Analysis

Holmgren, Rachelle 01 January 2016 (has links)
Extracting meaningful insights from massive datasets to help guide business decisions requires specialized skills in data analysis. Unfortunately, the supply of these skills does not meet the demand, due to the massive amount of data generated by society each day. This leaves businesses with a large amount of unanalyzed data that could have been used to support business decision making. Automating the process of analyzing this data would help address many companies' key challenge of a lack of appropriate analytical skills. This paper examines the process and challenges in automating this analysis of data. Central challenges include removing outliers without context, transforming data to a format that is compatible with the analysis method that will be used, and analyzing the results of the model.
270

TIME SYNCHRONIZATION IN FLIGHT TEST DATA ANALYSIS

Von Zuben, Francis S. G., David, Alfred S., Jr. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / A recurring problem in flight testing navigation systems is the need for an accurate, common time reference for the system under test and for the truth source to which it is compared. Lockheed Martin Aeronautics Company and Computer Sciences Corporation have developed software that utilizes all available timing information to reference the times of validity for each navigation measurement to Coordinated Universal Time. This permits accurate comparison and correlation of data necessary for statistical error analysis of the navigation system.

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