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Voltage fluctuations caused by rapidly changing loads, such as arc furnaces, can propagate to different parts of a power system. Although the flicker level at its origin can be high, levels that are measured at other sites are subject to attenuation, a process that is influenced by fault levels, transformer impedances, line impedances, and composition of the connected loads. This paper presents the methodology, measurement results, and data analysis in relation to synchronized flicker measurements carried out in a high-voltage (HV)/medium-voltage (MV) power system which contains an arc furnace supplied by a dedicated feeder connected to the HV busbar. The flicker transfer coefficients derived from measurement results clearly indicate that flicker transfer from the arc furnace site to the upstream HV busbar is governed by the fault levels at the two locations. However, the transfer of flicker from the upstream HV busbar to other downstream busbars is dependent on the downstream load composition. These flicker transfer coefficients are vital in the application of methodologies described in many reports and standards in relation to establishing planning levels at various voltage levels and in the allocation of flicker emission to customers. Index Terms--Flicker, flicker measurement, flicker transfer coefficient.

Developing user-friendly learning platform tailored to illustrating the integrative nature of specific subjects can be very effective in enhancing the involvement of students in the classroom. The focus of this paper is twofold; first, highlighting a specific project from a teaching perspective for the design and implementation of a multipurpose experimental test facility for plug-in electric vehicle, renewable energy and energy storage management in the smart grid context. Second, proposing the application of this project as an interactive tool to assist in demonstrating the system behaviour, when teaching the new emerging subjects in power engineering courses particularly, Smart Grid. Indeed, the scope of the test facility with the developed simulation tool is specially structured and oriented to education, training and research studies, where problem-based learning can be easily implemented. The electrical test hardware in this design can be operated independently as a multipurpose experimental setup for plug-in electric vehicle. In addition, it can also be interconnected with a small size wind or photovoltaic system to facilitate a complete hybrid integrated platform for testing and model verification. A variety of illustrative examples are presented to show the features of the test facility with its operation and how the components of this facility were selected. Additionally, several test scenarios are depicted using the developed simulation tool, which cover the assessment of grid integration with its components in the event of unforeseen circumstances. A recommendation that can be drawn from this paper is to motivate academics who are actively involved in conducting research on smart grid, to make use of their hardware or software designs in the process of teaching and learning so that undergraduate students can get the opportunity of observation and experimentation. In this sense, suggestions for future work are proposed. [ABSTRACT FROM AUTHOR]

In Australia and many other countries, distribution network service providers (DNSPs) have an obligation to their customers to provide electrical power that is reliable and of high quality. Failure to do so may have significant implications ranging from financial penalties theoretically through to the loss of a license to distribute electricity. In order to ensure the reliability and quality of supply are met, DNSPs engage in monitoring and reporting practice. This paper provides an overview of a large long-running power-quality monitoring project that has involved most of Australia's DNSPs at one time or another. This paper describes the challenges associated with conducting the project as well as some of the important outcomes and lessons learned. A number of novel reporting techniques that have been developed as part of the monitoring project are also presented. A discussion about large-volume data management, and issues related to reporting requirements in future distribution networks is included. [ABSTRACT FROM PUBLISHER]

Voltage dips are considered to be one of the costliest of all power quality disturbances due to their disruption of industrial and commercial operations. The ability to characterise the voltage dip performance of distribution networks has many benefits for industry. There is considerable potential for industry to make large economic gains if voltage dip behaviour can be better understood and planned for. To put strategies in place to deal with voltage dips, there is a need for extensive data collection and analysis so that correct planning decisions can be made. This study details the characteristics of voltage dip data which has been collected at low-voltage sites in Australia over a 9 year period. The data is displayed in a number of different formats to aid analysis. [ABSTRACT FROM AUTHOR]

Data perturbation aims to disguise original data values so the confidential information is kept safe and the disclosure risk is minimized. In this article, we exploit the characteristics of nonmetric multidimensional scaling (NMDS) to transform data and generate perturbed data. We hypothesize that NMDS is a good tool for privacy-preserving data clustering. For this, our model should preserve the distance between data objects (data utility in the context of clustering) whilst introducing enough uncertainty about the original data. We discuss privacy attacks in the context of disclosing the original data values and show that our method introduces uncertainty which could hinder the attacker from determining the exact location of points in the original space. We examine our model on a number of benchmark datasets and compare the results obtained from the perturbed data with those obtained from the original data using a number of clustering algorithms. We compare with other data perturbation techniques such as principal component analysis (PCA), random projection, single value decomposition and discrete cosine transform. We show that both NMDS and PCA produce the best utility preservation, obtaining clusterings of the perturbed data which are very similar to those on the original data. We also show that the transformation using NMDS introduces more uncertainty than other transformations in the point placement location and as the transformation is independent of the original data values it should produce enhanced privacy preservation. [ABSTRACT FROM AUTHOR]

BackgroundAdvances in mobile health (mHealth) technology have made it possible for patients and health care providers to monitor and track behavioral health symptoms in real time. Ideally, mHealth apps include both passive and interactive monitoring and demonstrate high levels of patient engagement. Digital phenotyping, the measurement of individual technology usage, provides insight into individual behaviors associated with mental health. ObjectiveResearchers at a Veterans Affairs Medical Center and Cogito Corporation sought to explore the feasibility and acceptability of an mHealth app, the Cogito Companion. MethodsA mixed methodological approach was used to investigate the feasibility and acceptability of the app. Veterans completed clinical interviews and self-report measures, at baseline and at a 3-month follow-up. During the data collection period, participants were provided access to the Cogito Companion smartphone app. The mobile app gathered passive and active behavioral health indicators. Data collected (eg, vocal features and digital phenotyping of everyday social signals) are analyzed in real time. Passive data collected include location via global positioning system (GPS), phone calls, and SMS text message metadata. Four primary model scores were identified as being predictive of the presence or absence of depression or posttraumatic stress disorder (PTSD). Veterans Affairs clinicians monitored a provider dashboard and conducted clinical outreach when indicated. ResultsFindings suggest that use of the Cogito Companion app was feasible and acceptable. Veterans (n=83) were interested in and used the app; however, active use declined over time. Nonetheless, data were passively collected, and outreach occurred throughout the study period. On the Client Satisfaction Questionnaire–8, 79% (53/67) of the sample reported scores demonstrating acceptability of the app (mean 26.2, SD 4.3). Many veterans reported liking specific app features (day-to-day monitoring) and the sense of connection they felt with the study clinicians who conducted outreach. Only a small percentage (4/67, 6%) reported concerns regarding personal privacy. ConclusionsFeasibility and acceptability of the Cogito Corporation platform to monitor mental health symptoms, behaviors, and facilitate follow-up in a sample of veterans were supported. Clinically, platforms such as the Cogito Companion system may serve as useful methods to promote monitoring, thereby facilitating early identification of risk and mitigating negative psychiatric outcomes, such as suicide.

The ITI curve developed by the Information Technology Industry Council (USA) describes an AC input voltage envelope, which typically can be tolerated by most information technology (IT) equipment supplied by nominal 120 V 60 Hz electricity networks. Although the curve ostensibly applies only to IT equipment supplied at 120 V 60 Hz it is often used throughout the electricity supply industry, including at other nominal voltages and frequencies, without modification or consideration of applicability to provide an indication of the input voltage tolerance of a wide range of equipment. This paper details a preliminary study aimed at developing an ITI style curve to suit 230 V 50 Hz electricity networks. A range of domestic and industrial equipment has been tested to determine voltage sag susceptibility. Overall, results for domestic appliances show that equipment connected to the Australian 230 V 50 Hz electricity network has voltage sag immunity considerably better than that defined by the ITI curve. The same may be said for the majority of industrial equipment tested. As such, the suitability of the ITI curve in describing a sag immunity envelope for individual pieces of equipment connected to 230 V 50 Hz electricity networks is highly questionable. [ABSTRACT FROM AUTHOR]

Museum exhibitions are literacy rich environments. Visitors may engage with a range of texts including texts that constitute the exhibition objects themselves, those that convey information about the objects and those that instruct visitors about how the visitors are expected by the museum to navigate through the exhibition. The ways in which visitors engage with these diverse texts are important defining factors of the visitors' museum experience. For museums, understanding how texts in their exhibitions are influencing the museum experience, and the possibility of a museum experience for the broad public community is important in the fulfilment of their public mission as cultural and education institutions. In this paper, we adopt a view of literacy as a social practice, the perspective of New Literacy Studies (NLS), that offers a fruitful way for museums to consider the interactions between exhibition texts and their audiences. Such considerations, we argue, can inform museums' approaches to broadening their visitor demographics to more strongly fulfill their public mission. We show that the goals of NLS resonate with some of the goals of the New Museology movement in museum studies, a movement that aims to democratize what museums represent and how. From NLS, we employ the concept of a literacy event to describe an exhibition visit through a literacy lens, and the concept of a literacy mediator to examine the literacy event not exclusively as an individual event, but a collectively produced event. The paper draws on data on how the literacy events of two groups of 'nontraditional' visitor groups were mediated in an exhibition, and show how they reveal the range of different literacies that visitors need to negotiate in a museum exhibition. [ABSTRACT FROM AUTHOR]