A fast acting electrical servo for the actuation of full span, Fowler-type wing flaps in DLC applications: A detail design study

The philosophy and detail design of an electro-mechanical actuator for Fowler-type wing flaps which have a response time constant of 0.025 seconds are described. A conventional electrical servomotor with a power rating twice the maximum power delivered to the load is employed along with adaptive, gain-scheduled feedback and various logic circuits, including one to remove electrical excitation from the motor during extended periods when no motion of the flap is desired

Assessing urban water sustainability in South Africa – not just performance measurement

Urban water management – and the impacts that rapid population growth, industrialisation and climate change are having on it – is gaining increasing attention worldwide. In South Africa (SA), cities are under pressure to respond to not only the challenges of water availability and quality, but also to economic transformation and social division. New solutions for improving the sustainability of cities need to be found, including the development of tools to guide decision-makers. Several benchmarking initiatives have been implemented in the SA water sector – mostly in terms of performance measurement of specific water services for regulatory purposes – but none provide an integrated analysis to enable a deeper understanding of sustainability. The research described in this paper was thus focused on using a systems approach to create an understanding of, and measure the potential for, sustainability in a South African urban water context. This has been achieved through the development and evaluation of a composite index, the Sustainability Index for Integrated Urban Water Management (SIUWM). The first step involved compiling a vision of sustainability for the SA water sector, and expanding it into a sustainability framework to help identify suitable indicators for the assessment process, as well as those which link with existing measurement initiatives. Key performance indicator results from the Department of Water Affairs’ Regulatory Performance Management System (RPMS) and the Blue Drop / Green Drop schemes were used as partial input to the SIUWM, and scores were computed for the nine member cities of the South African Cities Network (SACN). The SIUWM links the results from the regulatory systems with a broader sustainability assessment process to provide a more detailed analysis which can be used to establish goals and inform strategic processes to leverage support for improved water services. In this way, the connections that link the different aspects of urban water management can be used to generate a greater awareness of the underlying issues by key decision makers and thus guide appropriate action.Keywords: urban water management; sustainability index; performance measuremen

Free vibrations of thin-walled semicircular graphite-epoxy composite frames

A detailed study is made of the effects of variations in lamination and material parameters of thin walled composite frames on their vibrational characteristics. The structures considered are semicircular thin walled frames with I and J sections. The flanges and webs of the frames are modelled by using 2-D shell and plate finite elements. A mixed formulation is used with the fundamental unknowns consisting of both the generalized displacements and stress resultants in the frames. The frequencies and modes predicted by the 2-D finite element model are compared with those obtained from experiments, as well as with the predictions of a 1-D thin walled beam finite element model. A detailed study is made of the sensitivity of the vibrational response to variations in the fiber orientation, material properties of the individual layers, and boundary conditions

Australian anemones final report accompanied by attribution database of Australian anemones (on CD rom): prepared for the Department of Environment and Heritage, Heritage Division

This Final Report accompanies the "Attribution Database of Australian Anemones" on CD rom. The two works complete the project "Literature Review and Attribution of Australian Anemones" contracted to the Museum of Tropical Queensland. An Interim Report was submitted in February 2004. The report summarises findings from an investigation of specimen holdings of Australian anemones at seven major state museums in Australia. The findings are presented fully as line data in the accompanying attribution database for the Heritage section of the Department of Environment and Heritage. Sea anemones are marine animals related to corals and jellyfish. They occur in most habitats from intertidal to deep sea and have the potential to be used for recognition of Australian marine bio-regions. Their economic value includes biomedical potential, toxic properties, symbiotic relationships and the iconography of tropical coral reefs. A Checklist and Bibliography of Australian Anthozoa, developed by Museum of Tropical Queensland for the Australian Biological Information Facility (ABIF), documented the published occurrence of 84 valid species of anemones from 19 families in Australian waters. Our Interim Report singled out 23 of those 84 species for priority documentation as part of the present contract. Dr J. Wolstenholme targeted these and all other identified specimens from Australian waters in visits to the seven museums. This report includes descriptive profiles of the 23 prioritised species, in a format adaptable to web-page presentation, including brief description and picture, notes on behaviour and ecology and published references. This report notes that specimens and accompanying data for the 23 prioritised Australian anemone species and 38 of the 84 known species are held within the museums visited. The report records that specimens and data for 26 additional species not formally recorded from Australian waters were located within the museums, bringing the tally of known Australian anemone species to 110. The list of Australian anemones is expanded to include this information. This report records that the Attribution Database includes 730 specimens with 427 specimens confidently identified to species and 4 tentatively identified to species, with the remainder identified only to genus, family or class. This report also updates the following components of the Interim Report: background, species descriptions in web-page format, species list, classification and bibliography

Damage and repair classification in reinforced concrete beams using frequency domain data

This research aims at developing a new vibration-based damage classification technique that can efficiently be applied to a real-time large data. Statistical pattern recognition paradigm is relevant to perform a reliable site-location damage diagnosis system. By adopting such paradigm, the finite element and other inverse models with their intensive computations, corrections and inherent inaccuracies can be avoided. In this research, a two-stage combination between principal component analysis and Karhunen-Loéve transformation (also known as canonical correlation analysis) was proposed as a statistical-based damage classification technique. Vibration measurements from frequency domain were tested as possible damage-sensitive features. The performance of the proposed system was tested and verified on real vibration measurements collected from five laboratory-scale reinforced concrete beams modelled with various ranges of defects. The results of the system helped in distinguishing between normal and damaged patterns in structural vibration data. Most importantly, the system further dissected reasonably each main damage group into subgroups according to their severity of damage. Its efficiency was conclusively proved on data from both frequency response functions and response-only functions. The outcomes of this two-stage system showed a realistic detection and classification and outperform results from the principal component analysis-only. The success of this classification model is substantially tenable because the observed clusters come from well-controlled and known state conditions

Computational Methods for Crashworthiness

Presentations and discussions from the joint UVA/NASA Workshop on Computational Methods for Crashworthiness held at Langley Research Center on 2-3 Sep. 1992 are included. The presentations addressed activities in the area of impact dynamics. Workshop attendees represented NASA, the Army and Air Force, the Lawrence Livermore and Sandia National Laboratories, the aircraft and automotive industries, and academia. The workshop objectives were to assess the state-of-technology in the numerical simulation of crash and to provide guidelines for future research

Prospective observational study of point-of-care creatinine in trauma.

Background:Patients with trauma are at risk for renal dysfunction from hypovolemia or urological injury. In austere environments, creatinine values are not available to guide resuscitation. A new portable device, the Stat Sensor Point-of-care (POC) Whole Blood Creatinine Analyzer, provides accurate results in <30 s and requires minimal training. This device has not been evaluated in trauma despite the theoretical benefit it provides. The purpose of this study is to determine the clinical impact of the POC device in trauma. Methods:40 patients with trauma were enrolled in a prospective observational study. One drop of blood was used for creatinine determination on the Statsensor POC device. POC creatinine results were compared to the laboratory. Turnaround time (TAT) for POC and laboratory methods was calculated as well as time elapsed to CT scan if applicable. Results:Patients (n=40) were enrolled between December 2014 and March 2015. POC creatinine values were similar to laboratory methods with a mean bias of 0.075±0.27 (p=0.08). Mean analytical TATs for the POC measurements were significantly faster than the laboratory method (11.6±10.0 min vs 78.1±27.9 min, n=40, p<0.0001). Mean elapsed time before arrival at the CT scanner was 52.9±34.2 min. Conclusions:The POC device reported similar creatinine values to the laboratory and provided significantly faster results. POC creatinine testing is a promising development for trauma practice in austere environments and workup of a subset of stable patients with trauma. Further study is warranted to determine clinical impact, both in hospital-based trauma and austere environments

Development of guidance for sustainable irrigation use of greywater in gardens and small-scale agriculture in South Africa

Greywater is untreated household effluent from baths, showers, kitchen and hand-wash basins and laundry (i.e. all non-toilet uses). More than half of indoor household water is normally used for these purposes and can potentially be intercepted by the householder for additional beneficial uses. Greywater use is practised on an informal basis to supplement irrigation water, either in urban gardens in middle- to upper-income suburbs or in food gardens in lower-income informal, periurban and rural areas. It holds the potential to contribute significantly to food security in poor settlements by providing a source of both irrigation water and nutrients for crop plants. However, there are presently no formal guidelines for the use of greywater in South Africa. This paper presents the rationale and framework of a guidance document for the sustainable use of greywater to irrigate gardens and small-scale agriculture in South Africa, developed under the auspices of the Water Research Commission. The 3 driving principles in developing this guidance were: protection of human health; protection of plants irrigated; and protection of soil and the environment. Risk-management scenarios were developed on the basis of the extent of greywater characterisation. Water-quality constituents for inclusion were selected from among those indicated as presenting a problem in previous studies. Guidance was provided for managing greywater quality, either by mitigation of greywater quality (by practices such as irrigation method, amelioration of soil, leaching of soil and planting of tolerant plant types) or by small-scale biological treatment of greywater. Guidance was also given regarding the volumes of greywaterwhich can be applied, together with factors to adjust these volumes for site-specific conditions.Keywords: greywater, irrigation, food security, sustainable agriculture, health, soil, plant growt

Diarrhoea among children aged under five years and risk factors in informal settlements: a cross-sectional study in Cape Town, South Africa

Background: There is limited data on the association between diarrhoea among children aged under five years (U5D) and water use, sanitation, hygiene, and socio-economics factors in low-income communities. The study investigated U5D and the associated risk factors in the Zeekoe catchment in Cape Town, South Africa. Methods: A cross-sectional study was conducted in 707 households in six informal settlements (IS) two formal settlements (FS) (March-June 2017). Results: Most IS households used public taps (74.4%) and shared toilets (93.0%), while FS households used piped water on premises (89.6%) and private toilets (98.3%). IS respondents had higher average hand-washing scores than those of FS (0.04 vs