Doctor of Philosophy / This thesis presents a census of radio sources selected from the NRAO (National Radio Astronomy Observatory) VLA (Very Large Array) Sky Survey (NVSS) and Sydney University Molonglo Sky Survey (SUMSS) catalogues which have also been observed in the first data release of the 6 degree Field Galaxy Survey (6dFGS), a galaxy redshift survey of the local universe. Radio detections were found for 4,506 galaxies in the 6dFGS near-infrared-selected primary sample, a radio detection rate of 16%. A further 1,196 radio sources were observed by 6dF which were missing from the 6dFGS primary sample either because their host galaxies were too blue in colour or they appeared stellar on optical plates. The full sample comprises the largest and most homogeneous set of spectra and redshifts of radio sources in the local universe ever obtained. Results from the study of these objects form an accurate benchmark from which their cosmic evolution may be understood. 6dF spectra of galaxies have been used to determine the physical cause of radio emission from each object as either star formation or an active galactic nucleus powered by a super-massive black hole. These two classes of radio source have been characterised via a determination of the local radio luminosity function at 1.4 GHz; plotting the variation in their space density with luminosity. The star-formation density of the universe at the present epoch has been determined, the value of which which turns out to be in excellent agreement with previously published values. Fractional luminosity functions have also been determined showing that more massive galaxies have higher star-formation rates and are more likely to host a radio-loud AGN. The large-scale structure of star-forming galaxies and radio-loud AGN in the local universe has been studied by determining their clustering properties via the two-point correlation function. Radio-loud AGN are found to cluster more strongly than star-forming galaxies confirming that these objects are biased tracers of the underlying matter distribution. Both star-forming galaxies and AGNs cluster similarly to the underlying host galaxy population in which they reside. This thesis also describes the 843 MHz SUMSS catalogue, made by fitting elliptical Gaussians to sources in images. The catalogue contains radio sources to a limiting peak brightness of 6 mJy/beam at declination less than -50 degrees and 10 mJy/beam at declination greater than -50 degrees. Image artefacts have been classified using a novel technique involving a decision tree, which correctly identifies and rejects spurious sources in over 96% of cases and has ensured the catalogue is more than 95% complete and 90% reliable over most of its flux density range.

This thesis presents several observational studies based on radio variability and interstellar scintillation of extragalactic flat-spectrum radio sources. Such sources are commonly called blazars, a term used to describe the phenomenon observed when the jet of a radio-loud Active Galactic Nucleus (AGN) is directed towards the observer. These sources provide unique laboratories for studying the physics of relativistic jets. Observations of selected samples of blazars, made with the Australia Telescope Compact Array (ATCA) and the Australia Telescope Long Baseline Array are presented here. Statistics for long-term (months--years) and short-term (intraday) variability in both total and linearly polarized flux density at several frequencies are presented. The sensitivity and flux density measurement accuracy of the ATCA make it particularly useful for observations of intraday variability (IDV). Resolving the question of what is the mechanism for radio IDV was of great importance at the time this thesis was being undertaken, since if intrinsic, IDV implies extremely high brightness temperatures, far in excess of the Inverse Compton limit for incoherent synchrotron radiation. Most source models are fundamentally based on the assumption that the radiation from radio to optical, and sometimes soft X-ray, energies is produced by the incoherent synchrotron mechanism, so any result which challenges this has serious implications. There is now strong evidence that interstellar scintillation (ISS) is the principal cause of radio IDV, which substantially lowers the implied source brightness temperatures from those calculated assuming intrinsic variability. Some of the results presented in this thesis have made an important contribution to the paradigm shift from IDV to ISS, by showing unequivocally that the rapid IDV observed in PKS 1257-326 is a result of scintillation due to a nearby scattering screen in the ionised interstellar medium (ISM) of our Galaxy. This unusual source, serendipitously discovered during the course of my PhD, has also proved extremely valuable in showing that ISS can be used as a probe of microarcsecond-scale source structure and also of the local Galactic ISM. Such high angular resolution is not currently achievable even with space interferometer baselines. / Thesis (Ph.D.)--Physics, 2003.

The research background of this thesis is Radio Frequency Identification (RFID), where an object can be identified remotely using electromagnetic waves. The focus of this thesis is on the in-depth investigation of two major problems in the RFID deployment in supply chain applications, namely the reader collision problem in dense reader environments and the tag performance problem in hostile environments. To resolve the reader collision problem, the first part of this thesis offers a comprehensive path loss model for the analysis of the positioning of RFID reader antennas. Simulation software was developed to predict the signal strength at a certain distance from a reader antenna in a dense reader environment. This simulation software was also utilised to publish insights and research results in four major areas, which are: (i) Investigation on the sources of error in RFID simulation, to provide sensible and meaningful simulation results before actual deployment of RFID readers. (ii) The development of the idea of reader synchronisation, mainly to address the strict regulations imposed on the deployment of RFID readers in Europe. (iii) The determination of the threshold value for second carrier sensing in RFID, to enable the proper enforcement of second carrier sensing to avoid tag confusion in dense reader environments. (iv) The examination of Specific Absorption Rate (SAR) to ensure human safety in a dense RFID reader environment. The second part of this thesis addresses the RFID tag performance problem in hostile environments. The focus is on the development of HF and UHF tags, from the initial tag antenna design, tag antenna simulation, tag antenna prototyping and measurement, to the manufacturing of fully functional RFID tags at laboratory standards by combining RFID chips on to tag antennas. Though there are existing commercial grade HF and UHF RFID tags, they are mostly aimed at pallet level applications and are not suitable for deployment in hostile environments. The study cases presented in this thesis are mostly industrially driven, where there is a need to design specialty HF and UHF tag antennas. With a strong foundation in the development of HF and UHF RFID tags for various industrially driven applications, the research then concentrates on the development of a novel dual-frequency RFID antenna, which operates in both the HF and UHF regions. This dual-frequency RFID tag antenna embraces the benefits of both the HF and UHF tag antenna, which enable it to have a good read range while operating in environments that pose difficulties for RFID technology, for example applications in which ionised liquid is present, such as in cases of wine or bottled drinks. Several methodologies were used to develop a dual-frequency antenna, including the merging of HF and UHF antennas, and having a UHF resonance point on a typical HF antenna. With the successful development of an original dual-frequency antenna, the research was then expanded to miniaturise this dual-frequency antenna. The benefits of RFID deployment in supply chains are undoubtedly massive, though there are still issues and challenges to be resolved before a world-wide adoption is possible. This thesis contributes in recommending various reader antenna positioning and deployment techniques, and also contributes in developing HF tag antennas and UHF tag antennas for hostile environments, and a novel dual-frequency tag antenna to progress towards the aim of ubiquitous object identification. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1330885 / Thesis (Ph.D.) - University of Adelaide, School of Electrical and Electronic Engineering, 2008

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Thesis (M.S. in Telecommunication Systems Management)--Naval Postgraduate School, March 1990. / Thesis Advisor(s): Davidson, Kenneth L. Second Reader: Tulloch, A. W. "March 1990." Description based on signature page as viewed on August 26, 2009. DTIC Descriptor(s): Atmospheric Refraction, Very High Frequency, Ultrahigh Frequency, Communication And Radio Systems, Tools, Parameters, Wind, Forecasting, Accuracy, Theses, Electromagnetic Radiation, Pressure, Radiosondes, Refraction, Pacific Ocean, Climatology, Troposphere, Humidity, Gradients, Shores, East(Direction), Computer Printouts, Television Display Systems, Weather, Guided Missiles, Synoptic Meteorology, Test And Evaluation, Data Bases. DTIC Identifier(s): IREPS (Integrated Refractive Effect Prediction System). Author(s) subject terms: Communications, IREPS, refraction. Includes bibliographical references (p. 70-71). Also available online.

Thesis (M. Sc.)(Geology)--University of Pretoria, 2005. / Includes summary. Includes bibliographical references. Available on the Internet via the World Wide Web.

Spike Milligan has had an undisputable influence on English-language comedy in the past half-century. Monty Python’s Terry Jones cites the “free-wheeling fantasy world” Milligan created for the surreal radio series The Goon Show as the chief inspiration for his own group’s more internationally-famous work. However, Milligan’s writing for The Goon Show, which first aired between 1951 and 1960 displays a depth beyond “the confidence to be silly” noted by Python’s Michael Palin. Milligan’s scripts reveal a deliberate, if not wholly conscious, rejection of the laws of causality and probability, through frequent and systematic distortions of time and space. The fictional world revealed in The Goon Show’s corpus of half-hour stories is one in which concepts relating to time and space lack the fixed meanings that we attach to them in everyday life. Temporal and spatial relationships are fluid and indeterminate: boundaries between different times and different spaces can dissolve, allowing mutually inconsistent chronologies and scales of size and distance to coexist. The world-view underlying this is governed by an inversion of the generally-agreed-upon relationship between observable phenomena and individual perception. Rather than using the outside world as a source of data from which to construct models of ‘objective’ reality, Milligan allows his characters’ own words to modify the given conditions of any situation. This quasi-magical principle of storytelling mirrors cognitive strategies used by children in their primary-school years to grasp and describe the complexities of time and space. Childlike and lighthearted as it often is, The Goon Show’s twisting of time and space has a parallel to some highly complex ‘grown-up’ thinking. Its implicit rejection of the self-evidence of the fundamental laws of Newtonian physics recalls more than just the challenge to these laws provided by relativity and quantum mechanics. It also anticipates, by a full generation, the skeptical stance towards the self-evidence of immutable laws which forms the cornerstone of postmodern critiques of all fields of endeavour. The Goon Show reveals Spike Milligan to be an unsung visionary: always striding into unknown conceptual territory, he let his scripts, rather than a body of theoretical work, articulate his vision. Milligan’s comedic touch and his inimitable strangeness have led him to be appreciated, rather than studied. The ways in which The Goon Show turns time and space inward on themselves demonstrate, however, that the First Mover Unmoved in the mad universe of Goonery was an artistic and intellectual force to be reckoned with. Further study of Spike Milligan can only to lead to a greater appreciation of how far ahead of his time he truly was.

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In this thesis, we study the cognitive algorithm in digital television (DTV) bands for Wireless Regional Area Network (WRAN) signals. The WRAN standards are specified by the IEEE 802.22 Working Group. The principle of the proposed algorithm in this thesis is to recognize the band state by analyzing the transmitted signals in DTV bands. The received signals could be 4 possible options: 1.Noise 2.ATSC signal plus noise 3.WRAN signal plus noise 4.ATSC signal plus WRAN signal and noise. This thesis proposed an algorithm to cognize the WRAN signals, and the proposed schedule is 1.Cognitive algorithm for sensing ATSC signal 2.Cognitive algorithm for sensing WRAN signal. According to the result of this schedule, we will get the information of the band status. Later, WRAN will make use of cognitive radio technology we developed in the thesis, together with other cognitive information (such as channel capacity, system parameters, etc.), to sustain the WRAN signal transmission by making some adjustments of system parameters or the required bandwidth.