Zero phase sequence voltage injection for the alternate arm converter

The Alternate Arm Converter (AAC) is a voltage source converter being developed as an alternative to the Modular Multilevel Converter (MMC) for HVDC power transmission and reactive power compensation. Each Arm of the converter contains high voltage series IGBT Director Switches and full-bridge cells, which enables the VSC to ride through AC and DC network faults. This paper describes how the AAC can be optimised by modulating the converter terminal voltages with zerophase sequence triplen harmonic components. The optimisation reduces the ratio of the number of the full-bridge cells compared to the simpler Director Switches which offers a valuable improvement in footprint and efficiency

Linking Parental Wellbeing with the Wellbeing of Care Leaver and Care Experienced University Students: Analysing Relevance and Interconnections through the Lens of ‘Lived Lives’

This article analyses multidisciplinary research and theoretical perspectives on wellbeing, linking this with the findings from a narrative, biographical study of care-experienced university students in a UK university. In this paper, we examine the relevance of concepts of parental wellbeing, and wellbeing more generally, to \u27linked lives\u27\u27, defined as interrelated life events, experiences, memories and processes of narrativizing life histories both in and across time. While wellbeing is often depicted as an uplifting and uniformly positive concept in policy and research, it is also contested and opaque and is therefore difficult to define and operationalise. Elucidating young people\u27s voices on the complexity and \u27multilayeredness\u27 of everyday life events, we show that parental wellbeing, which is frequently negated from discussions of care experienced young people\u27s educational journeys requires greater critical scrutiny, arguing that temporalities and ever-changing personal and family histories indelibly affect individual care pathways for these young people. We thereby illuminate the significance of seemingly \u27ordinary\u27, everyday life events for care experienced students whilst showing how narrative interviews offer fruitful methodological approaches for understanding young people\u27s educational journeys

Modular 3D Interface Design for Accessible VR Applications

Designed with an accessible first design approach, the presented paper describes how exploiting humans proprioception ability in 3D space can result in a more natural interaction experience when using a 3D graphical user interface in a virtual environment. The modularity of the designed interface empowers the user to decide where they want to place interface elements in 3D space allowing for a highly customizable experience, both in the context of the player and the virtual space. Drawing inspiration from todays tangible interfaces used, such as those in aircraft cockpits, a modular interface is presented taking advantage of our natural understanding of interacting with 3D objects and exploiting capabilities that otherwise have not been used in 2D interaction. Additionally, the designed interface supports multimodal input mechanisms which also demonstrates the opportunity for the design to cross over to augmented reality applications. A focus group study was completed to better understand the usability and constraints of the designed 3D GUI.Comment: This preprint has not undergone peer review or any post-submission corrections. The Version of Record of this contribution will be published in Springer Nature Computer Science book series in Volume HCI International 202

The Alternate Arm Converter: A New Hybrid Multilevel Converter With DC-Fault Blocking Capability

This paper explains the working principles, supported by simulation results, of a new converter topology intended for HVDC applications, called the alternate arm converter (AAC). It is a hybrid between the modular multilevel converter, because of the presence of H-bridge cells, and the two-level converter, in the form of director switches in each arm. This converter is able to generate a multilevel ac voltage and since its stacks of cells consist of H-bridge cells instead of half-bridge cells, they are able to generate higher ac voltage than the dc terminal voltage. This allows the AAC to operate at an optimal point, called the “sweet spot,” where the ac and dc energy flows equal. The director switches in the AAC are responsible for alternating the conduction period of each arm, leading to a significant reduction in the number of cells in the stacks. Furthermore, the AAC can keep control of the current in the phase reactor even in case of a dc-side fault and support the ac grid, through a STATCOM mode. Simulation results and loss calculations are presented in this paper in order to support the claimed features of the AAC

CIAS-DM: A Model-Based, Human-Centered Architectural Modeling Method + Tool

A recent trend in architecture is for the built environment pro-actively contributes to enhancing human health, well-being, performance, and social interactions in measurable, predictable, and adaptable ways. Buildings are becoming interfaces and digital machines and their roles and capabilities are expanding. Accommodating this trend will require architectural design methods and tools to evolve. Sensing, monitoring, actuation, intelligence, and communication subsystems are now integral components of environmental designers’ vocabularies and considerations when designing space and form. At present, the theories, methods, and tools for representing and incorporating these elements during design do not exist. Developing these artifacts is an active area of research. This dissertation focuses on representing the affordances of complex, interactive, architectural systems (CIAS) and proposes, evaluates, and refines the Complex, Interactive, Architectural Systems Design Methodology (CIAS-DM). The purpose of CIAS-DM is to aid designers in making sure they understand the design challenge well at the start of the project. The Validation Square Research Design is used to evaluate CIAS-DM. Results are preliminary, but indicate that using a method similar to CIAS-DM may be useful for helping designers manage the scope of complex,interactive design challenges

The Oak Ridge National Security Complex: Human Health and the Environment as Casualties of Hot and Cold Wars

This report reviews lingering and emerging dangers at the largest NWC site, the Oak Ridge National Security Complex in Tennessee. The Oak Ridge site is both a high- value target for terrorist attack, a source of environmental contamination, and a potential public health threat. This report examines the nexus between environment, health and security at Oak Ridge, and discusses known and potential dangers in each of these areas. This research was completed money allocated during Round 5 of the Citizens’ Monitoring and Technical Assessment Fund (MTA Fund). Clark University was named conservator of these works. If you have any questions or concerns please contact us at [email protected]://commons.clarku.edu/globalgreen/1001/thumbnail.jp

The Death of a Nuclear Warhead: The Environmental and Health Impacts of Nuclear Weapons Complex Activities

Global Green USA is committed to the elimination of all weapons of mass destruction, and urges the government to continue disarmament efforts. The disassembly of nuclear weapons must, however, be conducted in a manner that minimizes danger to human health and the environment. There are a number of risks involved in disassembly, some unique, others similar to the dangers of the production of these weapons. Even low doses of fissile and other materials used in nuclear weapons, for instance, have been shown to pose serious risks to human health and the environment. This report examines these and other dangers, taking a particularly close look at the NWC’s Pantex Plant (Amarillo, Texas), where nuclear weapons slated for removal from the stockpile are disassembled. This research was completed money allocated during Round 4 of the Citizens’ Monitoring and Technical Assessment Fund (MTA Fund). Clark University was named conservator of these works. If you have any questions or concerns please contact us at [email protected]://commons.clarku.edu/globalgreen/1000/thumbnail.jp

HIGH LEVELS OF ENDURANCE TRAINING MITIGATE AGE-RELATED CHANGES IN RUNNING BIOMECHANICS – A LONGITUDINAL STUDY

Very few studies to date examined lower body and joint stiffness in ageing endurance runners, the majority cross-sectionally. The present study longitudinally examined age-related changes in leg and joint stiffness regulation in consistently trained master endurance runners, as well as the contribution of individual joints in resisting collapse and generating propulsion. Highly trained master endurance runners (N=10) were studied over a period of seven years whilst maintaining their training regime. Data was collected at mean age 53.54 ± 2.56 and 60.49 ± 2.56 following an identical overground running protocol, using a Kistler force plate and a 12-camera Vicon motion capture system. Following seven years of ageing, leg stiffness was unchanged. The athletes maintained similar magnitudes of joint stiffness and moment at the ankle and the hip whilst knee joint stiffness at amortisation increased by 0.60o-1 (

Scientific Reification

In the Embodied Earth installation, part of the Art and Light Exhibition held 15-30 August 2015 in the HD Skinner Annex of the Otago Museum in Dunedin, the viewer sensorially experiences lightning strikes in synchronicity with actual terrestrial lightning events occurring over a large swathe of the Earth’s surface via a live data stream. Viewers face a large projection screen on which they can see themselves in silhouette. My design intends the viewer to don a haptic jacket and move freely, as a live data stream, translated into animated lightning flashes, tracks the viewer’s screen position, appearing to strike the wearer’s upper body. In association with with the visual cue, the viewer would feel a strong vibration at the point of apparent lightning contact, concurrent with a synchronised subwoofer signal that pulsates their body with a short burst of low-frequency sound