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This paper proposes a novel data driven framework for detecting topology transitions in a distribution network. The framework analyzes data from phasor measurement units (PMUs) and relies on the fact that changes in network topology results in changes in the structure and admittance of the network. Using voltage and current phasors recorded by PMUs, the proposed method approximates network parameters using an ensemble-based deep learning model and thus, it does not require any knowledge of network parameters and load models. Using the prediction error of the proposed model, a connectivity matrix which shows the status of switches is constructed. In contrast to other methods, this proposed framework does not require a library of voltage and current transients associated with possible network transitions. It can also detect simultaneous switching actions and is robust to noise and load variations. The model yields a lower error detection rate, and its performance is validated using a modified version of the IEEE 33 bus network and a real feeder located in Queensland, Australia, under full and partial observability conditions. The proposed model has also been compared with another data driven method in terms of inference time and error detection rates. [ABSTRACT FROM AUTHOR]

Focusing on open forests and woodlands within the Injune Landscape Collaborative Project research area in central southeast Queensland, Australia, and using dual-pol (HH and HV) ALOS PALSAR repeat-pass InSAR data (temporal baseline of 92 days), this paper explores the detection of forest disturbance from the spaceborne repeat-pass InSAR correlation magnitude by developing a simple and efficient forest disturbance detection approach. In particular, a generic physical InSAR scattering model is derived by accounting for the forest disturbance information as well as the normal temporal decorrelation effects that are later compensated for using the modified Random Volume over Ground model. Based on the generic model, a quantitative indicator of forest disturbance is retrieved, namely, disturbance index that varies from 0 (no disturbance) to 1 (complete deforestation). This index is compared with that identified using a time series of Landsat sensor data over a selective logging area and has a relative root mean square error of 13% at a spatial resolution of 0.8 ha. This paper highlights the use of the co-pol InSAR correlation magnitude for forest disturbance detection, which serves as a complimentary application to using the cross-pol counterpart for forest height inversion in a companion work. Given the global availability of this type of data (e.g., Japanese Aerospace Exploration Agency’s ALOS-1/2 and NASA-ISRO’s NISAR), the method is anticipated to contribute to the range of tools being developed for large-scale forest disturbance assessment and monitoring. [ABSTRACT FROM AUTHOR]

This paper presents an evaluation of the inverted pendulum experiment in control engineering from a statistical and pedagogical point of view. Student usage statistics and success rates were collected over a period of three years at the University of Queensland, Brisbane, Australia. The results in the paper show that an online experiment can both increase student satisfaction and success rate while decreasing the costs to the university associated with a traditional laboratory setup. In particular, the number of laboratory benches has been reduced from seven to one. At the same time the number of laboratory contact hours for the course administrator was more than halved. [ABSTRACT FROM AUTHOR]

A generation planning framework is developed for a competitive, energy-only electricity market. The framework developed combines decentralized merchant investment plans stemming from market signals and technological preferences, with centralized resource planning concepts to decide optimal time-ordered investment decisions. The investment decisions maximize the new entrants' net surpluses and minimize the consumer interruption cost, accounting for many uncertain variables and technical details. The optimal plan given by the main centralized framework represents the system planner's solution derived from the set of decentralized plans. An illustrative case study is given in the paper, applying the proposed framework to the Queensland region of the National Electricity Market of Australia. [ABSTRACT FROM AUTHOR]

A calendar of international conferences, symposia, and workshops that the IEEE Computer Society sponsors or cooperates in presenting for July to September 2009 is presented, including the ISCC 2009, IEEE Symposium on Computers and Communications in Sousse, Tunisia, the ATC 2009, 6th lnternational Conference on Autonomic and Trusted Computing in Brisbane, Queensland and the CEC 2009, 11th IEEE Conference on Commerce and Enterprise Computing in Vienna, Austria.

Between February 1, 1997 and January 31, 1998, a 2.1 km vertically polarized 38 GHz communications link was studied in the subtropical city of Brisbane, Australia. According to the current ITU fading prediction method the link would be expected to experience a rainfall intensity of approximately 50 mm/h for 52.6 mm during the year, when averaged over a 60 s integration time. This should have caused approximately 20 dB of fading for 52.6 mm [1].-[3]. However the link actually experienced 20 dB of fading for 150.5 mm, with fading of 37 dB exceeded for 53.5 mm during the year. A rainfall intensity of 84 mm/h was exceeded for 64 mm at the receive end, and a rainfall intensity of 72 mm/h was exceeded for 52 min at the transmit end of the hop. [ABSTRACT FROM AUTHOR]

Focusing on a forest dominated by Poplar Box (Eucalyptus populnea) near Injune in Queensland, Australia, light detection and ranging (LiDAR) and optical remote sensing data are integrated with tree- and stand-level information to parameterize a coherent L-band synthetic aperture radar (SAR) imaging simulation that models microwave penetration and interaction with the canopy, understory, and ground. The approach used LiDAR data to generate a three-dimensional representation of the distribution of tree components (leaves and small branches) by species (based on 1-m³ voxels) and the ground surface. Tree trunks were mapped across a 7.5-ha forest stand using a LiDAR-derived height-scaled crown openness index. Primary and secondary branches were modeled as tapering cylinders and linked the canopy voxels to the LiDAR trunks. The dimensions of vegetation and soil components and their geometric and dielectric properties required by the model were calibrated with field-based measurements. Visual and numerical comparison between NASA JPL Airborne SAR data and the model simulation suggests the effective modeling of SAR imagery at L-band. The study provides a proof-of-concept approach for integrating LiDAR data in the parameterization of coherent SAR simulation models, and the model presents options for better understanding of the information content of SAR data in real forest situations. [ABSTRACT FROM AUTHOR]

The potential of synthetic aperture radar (SAR) data for retrieving the above-ground and component (e.g., branch, trunk) biomass of mixed-species forests (including woodlands) typical to subtropical Queensland, Australia, was evaluated using a wave scattering model based on that of Durden et al. (1989). The model was parameterized using field data collected for nine forest types, which were selected through combined analysis of 1: 4000 aerial photographs and light detection and ranging data. The simulated SAR backscatter data demonstrated a good correspondence at most frequencies and polarizations with Airborne SAR data. Analysis of scattering mechanisms revealed dominance of C-band horizontal-vertical (HV) volume scattering and increases with small-branch/foliage biomass, dominance of L- and P-band RH trunk-ground scattering and increases with trunk biomass, and dominance of L-band HV volume (branch) scattering and increases with large-branch biomass. The study concluded that above-ground biomass estimated using empirical relationships with selected SAR channels will be more reliable for forests of similar structural form due to dominance of microwave interaction with particular biomass components and the strength and consistency of relationships between these and the affiliated components that represent the total. In mixed-species forests, retrieval will be compromised by interaction with a greater diversity of structures and variability in relationships between structural components. Although empirical relationships with selected combinations of channels (e.g., L-band HH/HV) might allow retrieval of component and total biomass of forests containing trees of similar form (e.g., as mapped using Landsat sensor data), the use of SAR inversion models was considered a more appropriate route for retrieving the biomass of forests containing a mix of structural forms. [ABSTRACT FROM AUTHOR]

Studies the application of Semantic Web technology to optimize fuel cell design in Queensland. Overview of Semantic Web technology; Application of ontologies and semantic inferencing; Extension and refinement of existing Semantic Web technology; Use in knowledge mining in the materials engineering domain. INSET: Hydrogen Power..