Static accuracy and precision of heavy vehicle on-board mass systems

Objective • Feasibility programme for on-board mass (OBM) monitoring of heavy vehicles (HVs) • Australian road authorities through Transport Certification Australia (TCA) • Accuracy of contemporary, commercially-available OBM units in Australia • Results need to be addressed/incorporated into specifications for Stage 2 of Intelligent Access Program (IAP) by Transport Certification Australia

Developing regional precise positioning services using the legacy and future GNSS receivers

This paper presents an overview of technical solutions for regional area precise GNSS positioning services such as in Queensland. The research focuses on the technical and business issues that currently constrain GPS-based local area Real Time Kinematic (RTK) precise positioning services so as to operate in future across larger regional areas, and therefore support services in agriculture, mining, utilities, surveying, construction, and others. The paper first outlines an overall technical framework that has been proposed to transition the current RTK services to future larger scale coverage. The framework enables mixed use of different reference GNSS receiver types, dual- or triple-frequency, single or multiple systems, to provide RTK correction services to users equipped with any type of GNSS receivers. Next, data processing algorithms appropriate for triple-frequency GNSS signals are reviewed and some key performance benefits of using triple carrier signals for reliable RTK positioning over long distances are demonstrated. A server-based RTK software platform is being developed to allow for user positioning computations at server nodes instead of on the user's device. An optimal deployment scheme for reference stations across a larger-scale network has been suggested, given restrictions such as inter-station distances, candidates for reference locations, and operational modes. For instance, inter-station distances between triple-frequency receivers can be extended to 150km, which doubles the distance between dual-frequency receivers in the existing RTK network designs.

Theory and development of GPS integrity monitoring system

This thesis discusses various aspects of the integrity monitoring of GPS applied to civil aircraft navigation in different phases of flight. These flight phases include en route, terminal, non-precision approach and precision approach. The thesis includes four major topics: probability problem of GPS navigation service, risk analysis of aircraft precision approach and landing, theoretical analysis of Receiver Autonomous Integrity Monitoring (RAIM) techniques and RAIM availability, and GPS integrity monitoring at a ground reference station. Particular attention is paid to the mathematical aspects of the GPS integrity monitoring system. The research has been built upon the stringent integrity requirements defined by civil aviation community, and concentrates on the capability and performance investigation of practical integrity monitoring systems with rigorous mathematical and statistical concepts and approaches. Major contributions of this research are: • Rigorous integrity and continuity risk analysis for aircraft precision approach. Based on the joint probability density function of the affecting components, the integrity and continuity risks of aircraft precision approach with DGPS were computed. This advanced the conventional method of allocating the risk probability. • A theoretical study of RAIM test power. This is the first time a theoretical study on RAIM test power based on the probability statistical theory has been presented, resulting in a new set of RAIM criteria. • Development of a GPS integrity monitoring and DGPS quality control system based on GPS reference station. A prototype of GPS integrity monitoring and DGPS correction prediction system has been developed and tested, based on the A USN A V GPS base station on the roof of QUT ITE Building.

Positioning refugee students as intellectual class members

This chapter looks at the 'smart links' and 'smart paths' created by some English as a second language (ESL) teachers to enable refugee students with little, no or severely interrupted schooling to participate in class after re-settlement in the West. Data are drawn from an interview study conducted in an intensive English language school for adolescents and three mainstream high schools. Findings show how teachers who rejected deficit discourses enabled student participation in the intellectual work of the classroom. The Bourdieusian concept of capital is used to describe teacher competence for diverse classrooms in a world of student mobility and unequal educational access.

Destination competitiveness through the lens of brand positioning : the case of Australia’s Sunshine Coast

The purpose of the paper is to provide a collaborative practitioner/academic interpretation of a destination’s competitiveness through the lens of brand positioning in the domestic short break drive market. A 173 item questionnaire, which was mailed to a systematic random sample of 3000 households in the target market, attracted a 17% useable response. The paper compares how one destination, the Sunshine Coast, is positioned in its most important market, in relation to the brand identity intended by the destination marketing organisation (DMO). Key constructs were brand salience, brand associations and brand resonance. The Sunshine Coast was found to hold a leadership position in the minds of consumers, and the results indicated a strong level of congruence between actual market perceptions and the brand identity intended by the DMO. There were strong associations between brand salience, brand associations and brand resonance. The findings provided the destination of interest with both a measure of past marketing effectiveness as well as positive indicators of future performance. The paper represents collaboration between a tourism practitioner and a tourism academic, and attempts a contribution to the emerging literature on destination competitiveness through the lens of positioning theory.

Destination positioning opportunities elicited through the repertory test with laddering analysis

While in many travel situations consumers have an almost limitless range of destinations to choose from, their actual decision set will usually only comprise between two and six destinations. One of the greatest challenges facing destination marketers is positioning their destination, against the myriad of competing places that offer similar features, into consumer decision sets. Since positioning requires a narrow focus, marketing communications must present a succinct and meaningful proposition, the selection of which is often problematic for destination marketing organisations (DMO), which deal with a diverse and often eclectic range of attributes in addition to numerous self-interested and demanding stakeholders. This paper reports the application of two qualitative techniques used to explore the range of cognitive attributes, consequences and personal values that represent potential positioning opportunities in the context of short break holidays. The Repertory Test is an effective technique for understanding the salient attributes used by a traveller to differentiate destinations, while Laddering Analysis enables the researcher to explore the smaller set of personal values guiding such decision making. A key finding of the research was that while individuals might vary in their repertoire of salient attributes, there was a commonality of shared consequences and values.

The relationship between strategic positioning and perceived value of social networking sites

The use of social networking sites (SNS) by online citizens to share photos, update friends, play games and to connect with the world has exploded, with SNS and blogs now eclipsing email traffic (eMarketer 2009). Just one popular application on one SNS, (Farmville on Facebook) acquired more than 63 million users since its launch in June 2009 (Marketing 2009. The major global social networks are Facebook, Twitter, YouTube and MySpace, with Facebook claiming that it passed 350 million users in November (Marketing 2009). As usage increases and competition intensifies, the major sites must strategically position themselves to develop a competitive advantage in order to maintain or grow their share of the pie. So how do the major SNS position their brands, and do users perceive significant differences among the big players? This presentation answers these questions by reporting the results of an empirical study of SNS usage by Australian adults. Like other brands, aligning brand positioning strategies with user knowledge and perceptions of SNS is an important ingredient to achieving success (Keller 1993). Furthermore we compare the types of value for three different SNS to identify the relationships between the value derived by users and the stated positioning of the site.

Geometry‐specified troposphere decorrelation for subcentimeter real‐time kinematic solutions over long baselines

Real‐time kinematic (RTK) GPS techniques have been extensively developed for applications including surveying, structural monitoring, and machine automation. Limitations of the existing RTK techniques that hinder their applications for geodynamics purposes are twofold: (1) the achievable RTK accuracy is on the level of a few centimeters and the uncertainty of vertical component is 1.5–2 times worse than those of horizontal components and (2) the RTK position uncertainty grows in proportional to the base‐torover distances. The key limiting factor behind the problems is the significant effect of residual tropospheric errors on the positioning solutions, especially on the highly correlated height component. This paper develops the geometry‐specified troposphere decorrelation strategy to achieve the subcentimeter kinematic positioning accuracy in all three components. The key is to set up a relative zenith tropospheric delay (RZTD) parameter to absorb the residual tropospheric effects and to solve the established model as an ill‐posed problem using the regularization method. In order to compute a reasonable regularization parameter to obtain an optimal regularized solution, the covariance matrix of positional parameters estimated without the RZTD parameter, which is characterized by observation geometry, is used to replace the quadratic matrix of their “true” values. As a result, the regularization parameter is adaptively computed with variation of observation geometry. The experiment results show that new method can efficiently alleviate the model’s ill condition and stabilize the solution from a single data epoch. Compared to the results from the conventional least squares method, the new method can improve the longrange RTK solution precision from several centimeters to the subcentimeter in all components. More significantly, the precision of the height component is even higher. Several geosciences applications that require subcentimeter real‐time solutions can largely benefit from the proposed approach, such as monitoring of earthquakes and large dams in real‐time, high‐precision GPS leveling and refinement of the vertical datum. In addition, the high‐resolution RZTD solutions can contribute to effective recovery of tropospheric slant path delays in order to establish a 4‐D troposphere tomography.

Destination positioning opportunities using personal values : elicited through the Repertory Test with Laddering Analysis

While in many travel situations there is an almost limitless range of available destinations, travellers will usually only actively consider two to six in their decision set. One of the greatest challenges facing destination marketers is positioning their destination, against the myriad of competing places that offer similar features, into consumer decision sets. Since positioning requires a narrow focus, marketing communications must present a succinct and meaningful proposition, the selection of which is often problematic for destination marketing organisations (DMO), which deal with a diverse and often eclectic range of attributes in addition to self-interested and demanding stakeholders who have interests in different market segments. This paper reports the application of two qualitative techniques used to explore the range of cognitive attributes, consequences and personal values that represent potential positioning opportunities in the context of short break holidays. The Repertory Test is an effective technique for understanding the salient attributes used by a traveller to differentiate destinations, and Laddering Analysis enables the researcher to explore the smaller set of consequences and personal values guiding such decision making. A key finding of the research was that while individuals might vary in their repertoire of salient attributes, there was a commonality of shared consequences and values. This has important implications for DMOs, since a brand positioning theme that is based on a value will subsume multiple and diverse attributes. It is posited that such a theme will appeal to a broader range of travellers, as well as appease a greater number of destination stakeholders, than would an attribute based theme.

Aerial SLAM with a single camera using visual expectation

Micro aerial vehicles (MAVs) are a rapidly growing area of research and development in robotics. For autonomous robot operations, localization has typically been calculated using GPS, external camera arrays, or onboard range or vision sensing. In cluttered indoor or outdoor environments, onboard sensing is the only viable option. In this paper we present an appearance-based approach to visual SLAM on a flying MAV using only low quality vision. Our approach consists of a visual place recognition algorithm that operates on 1000 pixel images, a lightweight visual odometry algorithm, and a visual expectation algorithm that improves the recall of place sequences and the precision with which they are recalled as the robot flies along a similar path. Using data gathered from outdoor datasets, we show that the system is able to perform visual recognition with low quality, intermittent visual sensory data. By combining the visual algorithms with the RatSLAM system, we also demonstrate how the algorithms enable successful SLAM.

Use of precision time protocol to synchronize sampled value process buses

Transmission smart grids will use a digital platform for the automation of high voltage substations. The IEC 61850 series of standards, released in parts over the last ten years, provide a specification for substation communications networks and systems. These standards, along with IEEE Std 1588-2008 Precision Time Protocol version 2 (PTPv2) for precision timing, are recommended by the both IEC Smart Grid Strategy Group and the NIST Framework and Roadmap for Smart Grid Interoperability Standards for substation automation. IEC 61850, PTPv2 and Ethernet are three complementary protocol families that together define the future of sampled value digital process connections for smart substation automation. A time synchronisation system is required for a sampled value process bus, however the details are not defined in IEC 61850-9-2. PTPv2 provides the greatest accuracy of network based time transfer systems, with timing errors of less than 100 ns achievable. The suitability of PTPv2 to synchronise sampling in a digital process bus is evaluated, with preliminary results indicating that steady state performance of low cost clocks is an acceptable ±300 ns, but that corrections issued by grandmaster clocks can introduce significant transients. Extremely stable grandmaster oscillators are required to ensure any corrections are sufficiently small that time synchronising performance is not degraded.