7,423 research outputs found

    Circumferential pressure distributions in a model labyrinth seal

    Get PDF
    A research program to isolate and study leakage flow through labyrinth glands was initiated. Circumferential pressure distributions were measured in the labyrinth glands with geometry appropriate to the high pressure labyrinths in large steam turbines. Knowledge of this pressure distribution is essential as it is this unequal pressure field that results in the destabilizing force. Parameters that are likely to affect the pressure distributions are incorporated into the test rig. Some preliminary pressure profiles are presented

    Experimental investigation of lateral forces induced by flow through model labyrinth glands

    Get PDF
    The lateral forces induced by flow through model labyrinth glands were investigated. Circumferential pressure distributions, lateral forces and stiffness coefficients data obtained are discussed. The force system is represented as a negative spring and a tangential force orthogonal to eccentricity. The magnitude of these forces are dependent on eccentricity, entry swirl, rotor peripheral velocity and seal size. A pressure equalization chamber at midgland tests should in significantly reduced forces and stiffness coefficients

    Whole-Lake Primary Production Calculator

    Get PDF
    This work describes an implementation of a model for estimation of both benthic and phytoplanktonic primary production in lakes. The web application makes use of interpolation techniques to allow estimates of primary production using values for photosynthesis/irradiance parameters at only 5 depths. These estimates compare favorably in accuracy with estimates using values listed at over one hundred depths. Validation of the implementation was done by comparison with primary production results from the Northern Temperate Lakes Long Term Ecological Research database

    Development and validation of the crew-station system-integration research facility

    Get PDF
    The various issues associated with the use of integrated flight management systems in aircraft were discussed. To address these issues a fixed base integrated flight research (IFR) simulation of a helicopter was developed to support experiments that contribute to the understanding of design criteria for rotorcraft cockpits incorporating advanced integrated flight management systems. A validation experiment was conducted that demonstrates the main features of the facility and the capability to conduct crew/system integration research

    “I don’t care about Asia”: teaching Asia in Australia

    Get PDF
    Past the critiques of static contexts and hermetic conceptualisations of sociocultural communities, this paper argues that an important part of the work that remains to be done in Asian Australian studies is at the other frontline part of academia – teaching. In a world of contrarily increasing mobility and cultural apathy, how do we ‘sell’ the relevance of ‘Asia’ to students without resorting to the discourses of Asia as ‘the exotic other’ and/or as a market. In what ways can ‘Asia literacy’ be interpreted for a student body whose identities are becoming both more complex and syncretic? We suggest that university teachers are uniquely positioned to equip students with an understanding of Asia that is more processual than factual and more attitudinal than learnt. Drawing on the experience of teaching over a decade in Perth and Brisbane, we reflect on how the task has changed over the years, what the typical obstacles/barriers faced are and what students understand Asia literacy to mean in the midst of the current political and media discourses surrounding Asia today. Finally, we reflect on how our own experiences of such teaching emerges from our own sense of being and belonging as Australians of Asian origins

    Haze in the Klang Valley of Malaysia

    Get PDF
    Continuous measurements of dry aerosol light scattering (Bsp) were made at two sites in the Klang Valley of Malaysia between December 1998 and December 2000. In addition 24-h PM2.5 samples were collected on a one-day-in-six cycle and the chemical composition of the aerosol was determined. Periods of excessive haze were defined as 24-h average Bsp values greater than 150 Mm-1 and these occurred on a number of occasions, between May and September 1999, during May 2000, and between July and September 2000. The evidence for smoke being a significant contributor to aerosol during periods of excessive haze is discussed and includes features of the aerosol chemistry, the diurnal cycle of Bsp, and the coincidence of forest fires on Sumatra during the southwest (SW) monsoon period, as well as transport modelling for one week of the southwest Monsoon of 2000. The study highlights that whilst transboundary smoke is a major contributor to poor visibility in the Klang Valley, smoke from fires on Peninsular Malaysia is also a contributor, and at all times, the domestic source of secondary particle production is present

    Stress and Emotion Classification Using Jitter and Shimmer Features

    Get PDF
    In this paper, we evaluate the use of appended jitter and shimmer speech features for the classification of human speaking styles and of animal vocalization arousal levels. Jitter and shimmer features are extracted from the fundamental frequency contour and added to baseline spectral features, specifically Mel-frequency cepstral coefficients (MFCCs) for human speech and Greenwood function cepstral coefficients (GFCCs) for animal vocalizations. Hidden Markov models (HMMs) with Gaussian mixture models (GMMs) state distributions are used for classification. The appended jitter and shimmer features result in an increase in classification accuracy for several illustrative datasets, including the SUSAS dataset for human speaking styles as well as vocalizations labeled by arousal level for African elephant and Rhesus monkey species

    Applications of 3D printing in the management of severe spinal conditions

    Get PDF
    The latest and fastest-growing innovation in the medical field has been the advent of three-dimensional printing technol- ogies, which have recently seen applications in the production of low-cost, patient-specific medical implants. While a wide range of three-dimensional printing systems has been explored in manufacturing anatomical models and devices for the medical setting, their applications are cutting-edge in the field of spinal surgery. This review aims to provide a com- prehensive overview and classification of the current applications of three-dimensional printing technologies in spine care. Although three-dimensional printing technology has been widely used for the construction of patient-specific ana- tomical models of the spine and intraoperative guide templates to provide personalized surgical planning and increase pedicle screw placement accuracy, only few studies have been focused on the manufacturing of spinal implants. Therefore, three-dimensional printed custom-designed intervertebral fusion devices, artificial vertebral bodies and disc substitutes for total disc replacement, along with tissue engineering strategies focused on scaffold constructs for bone and cartilage regeneration, represent a set of promising applications towards the trend of individualized patient care
    corecore