An optimization-based algorithm for shunt active filter under distorted supply voltages

When the supply voltages are balanced and sinusoidal, load compensation can give both unity power factor (UPF) and perfect harmonic cancellation (PHC) source currents. But under distorted supply voltages, achieving both UPF and PHC currents are not possible and contradictory to each other. Hence there should be an optimal performance between these two important compensation goals. This paper presents an optimal control algorithm for load compensation under unbalanced and distorted supply voltages. In this algorithm source currents are compensated for reactive, imbalance components and harmonic distortions set by the limits. By satisfying the harmonic distortion limits and power balance, this algorithm gives the source currents which will provide the maximum achievable power factor. The detailed simulation results using MATLAB are presented to support the performance of the proposed optimal control algorithm.

Design of a capacitor supported dynamic voltage restorer (DVR) for unbalanced and distorted loads

The paper discusses the operating principles and control characteristics of a dynamic voltage restorer (DVR) that protects sensitive but unbalanced and/or distorted loads. The main aim of the DVR is to regulate the voltage at the load terminal irrespective of sag/swell, distortion, or unbalance in the supply voltage. In this paper, the DVR is operated in such a fashion that it does not supply or absorb any active power during the steady-state operation. Hence, a DC capacitor rather than a DC source can supply the voltage source inverter realizing the DVR. The proposed DVR operation is verified through extensive digital computer simulation studies.

Playpolis : transyouth and urban networking in Seoul

The overarching aim of this study is to create new knowledge about how playful interactions (re)create the city via ubiquitous technologies, with an outlook to apply the knowledge for pragmatic innovations in relevant fields such as urban planning and technology development in the future. The study looks at the case of transyouth, the in-between demographic bridging youth and adulthood in Seoul, one of the most connected, densely populated, and quickly transforming metropolises in the world. To unravel the elusiveness of ‘play’ as a subject and the complexity of urban networks, this study takes a three-tier transdisciplinary approach comprised of an extensive literature review, Shared Visual Ethnography (SVE), and interviews with leading industry representatives who design and develop the playscape for Seoul transyouth. Through these methodological tools, the study responds to the following four research aims: 1. Examine the sociocultural, technological, and architectural context of Seoul 2. Investigate Seoul transyouth’s perception of the self and their technosocial environment 3. Identify the pattern of their playful interaction through which meanings of the self and the city are recreated 4. Develop an analytical framework for enactment of play This thesis argues that the city is a contested space that continuously changes through multiple interactions among its constituents on the seam of control and freedom. At the core of this interactive (re)creation process is play. Play is a phenomenon that is enacted at the centre of three inter-related elements of pressure, possibility, and pleasure, the analytical framework this thesis puts forward as a conceptual apparatus for studying play across disciplines. The thesis concludes by illustrating possible trajectories for pragmatic application of the framework for envisioning and building the creative, sustainable, and seductive city.

Digital constitutionalism and the role of the rule of law in the governance of virtual communities

This project proposes a new conceptual framework for the regulation of social networks and virtual communities. By applying a model based upon the rule of law, this thesis addresses the growing tensions that revolve around the public use of private networks. This research examines the shortcomings of traditional contractual governance models and cyberlaw theory and provides a reconstituted approach that will allow public constitutional-type interests to be recognised in the interpretation and enforcement of contractual doctrine.

Model interoperability in building information modelling

The exchange of design models in the design and construction industry is evolving away from 2-dimensional computer-aided design (CAD) and paper towards semantically-rich 3-dimensional digital models. This approach, known as Building Information Modelling (BIM), is anticipated to become the primary means of information exchange between the various parties involved in construction projects. From a technical perspective, the domain represents an interesting study in model-based interoperability, since the models are large and complex, and the industry is one in which collaboration is a vital part of business. In this paper, we present our experiences with issues of model-based interoperability in exchanging building information models between various tools, and in implementing tools which consume BIM models, particularly using the industry standard IFC data modelling format. We report on the successes and challenges in these endeavours, as the industry endeavours to move further towards fully digitised information exchange.

On the feasibility of using servo-mechanisms in wireless multimedia sensor network deployments

This paper considers the use of servo-mechanisms as part of a tightly integrated homogeneous Wireless Multi- media Sensor Network (WMSN). We describe the design of our second generation WMSN node platform, which has increased image resolution, in-built audio sensors, PIR sensors, and servo- mechanisms. These devices have a wide disparity in their energy consumption and in the information quality they return. As a result, we propose a framework that establishes a hierarchy of devices (sensors and actuators) within the node and uses frequent sampling of cheaper devices to trigger the activation of more energy-hungry devices. Within this framework, we consider the suitability of servos for WMSNs by examining the functional characteristics and by measuring the energy consumption of 2 analog and 2 digital servos, in order to determine their impact on overall node energy cost. We also implement a simple version of our hierarchical sampling framework to evaluate the energy consumption of servos relative to other node components. The evaluation results show that: (1) the energy consumption of servos is small relative to audio/image signal processing energy cost in WMSN nodes; (2) digital servos do not necessarily consume as much energy as is currently believed; and (3) the energy cost per degree panning is lower for larger panning angles.

Combination of Kalman filter and least error square techniques in power system

An algorithm based on the concept of combining Kalman filter and Least Error Square (LES) techniques is proposed in this paper. The algorithm is intended to estimate signal attributes like amplitude, frequency and phase angle in the online mode. This technique can be used in protection relays, digital AVRs, DGs, DSTATCOMs, FACTS and other power electronics applications. The Kalman filter is modified to operate on a fictitious input signal and provides precise estimation results insensitive to noise and other disturbances. At the same time, the LES system has been arranged to operate in critical transient cases to compensate the delay and inaccuracy identified because of the response of the standard Kalman filter. Practical considerations such as the effect of noise, higher order harmonics, and computational issues of the algorithm are considered and tested in the paper. Several computer simulations and a laboratory test are presented to highlight the usefulness of the proposed method. Simulation results show that the proposed technique can simultaneously estimate the signal attributes, even if it is highly distorted due to the presence of non-linear loads and noise.

Urban growth monitoring techniques for sustainable development

This paper discusses the role of advance techniques for monitoring urban growth and change for sustainable development of urban environment. It also presents results of a case study involving satellite data for land use/land cover classification of Lucknow city using IRS-1C multi-spectral features. Two classification algorithms have been used in the study. Experiments were conducted to see the level of improvement in digital classification of urban environment using Artificial Neural Network (ANN) technique.

Lift@Weimar : sustainable interaction with food, technology, and the city (Workshop)

This workshop explores innovative approaches to understanding and cultivating sustainable food culture in urban environments via human-computer-interaction (HCI) design and ubiquitous technologies. We perceive the city as an intersecting network of people, place, and technology in constant transformation. Our 2009 OZCHI workshop, Hungry 24/7? HCI Design for Sustainable Food Culture, opened a new space for discussion on this intersection amongst researchers and practitioners from diverse backgrounds including academia, government, industry, and non-for-profit organisations. Building on the past success, this new instalment of the workshop series takes a more refined view on mobile human-food interaction and the role of interactive media in engaging citizens to cultivate more sustainable everyday human-food interactions on the go. Interactive media in this sense is distributed, pervasive, and embedded in the city as a network. The workshop addresses environmental, health, and social domains of sustainability by bringing together insights across disciplines to discuss conceptual and design approaches in orchestrating mobility and interaction of people and food in the city as a network of people, place, technology, and food.

Incorporating community history into urban redevelopment

A community history project must be relevant to each person within it so that they see themselves as part of the socio-cultural fabric of the area and feel a sense of ownership of their environment. The Mill Albion community history project is a diverse, multi-layered public history/art program that captures the social heritage of The Mill Albion and allows the community to contribute to their ongoing history. The Albion Flour Mill was built in 1930 at a time when Australia was feeling the effects of its worst economic depression and continued operations for more than 72 years. After ceasing operation in 2005 the site was left to deteriorate. The FKP Property Group purchased the land to undertake a new urban redevelopment project, drawing on the design principles of a traditional ‘village’, while valuing the importance of remembering the community that once included the Flour Mill. This paper reflects on the this project and showcases some of the culturally creative ways this community’s history was told, using methods such as digital stories, contemporary and historical photography and oral history.

A story worth telling : putting oral history and digital collections online in cultural institutions

Digital platforms in cultural institutions offer exciting opportunities for oral history and digital storytelling that can augment and enrich traditional collections. The way in which cultural institutions allow access to the public is changing dramatically, prompting substantial expansions of their oral history and digital story holdings. In Queensland, Australia, public libraries and museums are becoming innovative hubs of a wide assortment of collections that represent a cross-section of community groups and organisations through the integration of oral history and digital storytelling. The State Library of Queensland (SLQ) features digital stories online to encourage users to explore what the institution has in the catalogue through their website. Now SLQ also offers oral history interviews online, to introduce users to oral history and other components of their collections,- such as photographs and documents to current, as well as new users. This includes the various departments, Indigenous centres and regional libraries affiliated with SLQ statewide, who are often unable to access the materials held within, or even full information about, the collections available within the institution. There has been a growing demand for resources and services that help to satisfy community enthusiasm and promote engagement. Demand increases as public access to affordable digital media technologies increases, and as community or marginalised groups become interested in do it yourself (DIY) history; and SLQ encourages this. This paper draws on the oral history and digital story-based research undertaken by the Queensland University of Technology (QUT) for the State Library of Queensland including: the Apology Collection: The Prime Minister’s apology to Australia’s Indigenous Stolen Generation; Five Senses: regional Queensland artists; Gay history of Brisbane; and The Queensland Business Leaders Hall of Fame.

Deleuze and "The Intercessors"

The late French philosopher Gilles Deleuze has enjoyed significant notoriety and acclaim in American academia over the last 20 years. The unique disciplinary focus of the contemporary discussion has derived from Deleuze the architectural possibilities of biotechnology, systems theory, and digital processualism. While the persistence of Deleuze’s theory of science and the formalist readings of Mille Plateaux and Le Bergsonisme have dominated the reception since the 1990s, few are aware of a much earlier encounter between Deleuze and architects, beginning at Columbia University in the 1970s, which converged on the radical politics of Anti-OEdipus and its American reception in the journal Semiotext(e), through which architecture engaged a much broader discourse alongside artists, musicians, filmmakers, and intellectuals in the New York aesthetic underground, of which Deleuze and Félix Guattari were themselves a part.

Power network in loop : a paradigm for real-time simulation and hardware testing

This paper discusses a new paradigm of real-time simulation of power systems in which equipment can be interfaced with a real-time digital simulator. In this scheme, one part of a power system can be simulated by using a real-time simulator; while the other part is implemeneted as a physical system. The only interface of the physical system with the computer-based simulator is through data-acquisition system. The physical system is driven by a voltage-source converter (VSC)that mimics the power system simulated in the real-time simulator. In this papar, the VSC operates in a voltage-control mode to track the point of common coupling voltage signal supplied by the digital simulator. This type of splitting a network in two parts and running a real-time simulation with a physical system in parallel is called a power network in loop here. this opens up the possibility of study of interconnection o f one or several distributed generators to a complex power network. The proposed implementation is verified through simulation studies using PSCAD/EMTDC and through hardware implementation on a TMS320G2812 DSP.