396 research outputs found
The relevance of specific csfs for stakeholders during ERP implementation: an empirical study from Oman
The success of ERP systems implementation is affected by the extent to which stakeholders have been prepared for the project activities and its outcomes. Stakeholdersâ preparation needs change as the ERP implementation lifecycle progresses and varies across stakeholder groups. Therefore a dynamic model is needed for such preparation. However such a model needs to reflect the relevance of different CSFs to different stakeholder groups at different stages of the ERP implementation life-cycle. This study examines empirical evidence from a survey conducted in Omani organisations to determine what these individual CSFs are and how they are distributed across the ERP implementation life-cycle for different stakeholder groups. The CSFs included in the survey were derived from a structured review of literature. Purposive sampling was used to select respondents representing different ERP stakeholders groups, all respondents had both experience and knowledge of ERP implementations. The survey data are analysed and the distribution of relevant CSFs across the ERP lifecycle for the different stakeholder groups are presente
Labour Force Participation and Household Debt
In the past decade or so there has been a substantial rise in the indebtedness and debt-servicing obligations of Australian households. This has been accompanied by a trend increase in labour force participation (LFP) for women and more recently for men. Microeconomic data show a clear positive correlation between indebtedness and LFP. This paper models the LFP decision of prime-age Australian women and men accounting for the influence of debt and assets along with a range of other variables found to be important in the literature. The potential two-way causation between debt and labour supply is also addressed. Data from the Household, Income and Labour Dynamics in Australia (HILDA) Survey are used as it contains recent and detailed data on household wealth along with extensive labour market and demographic data. A cross-section model of LFP is estimated using the detailed measures of household debts and assets available in Wave 2 of the survey. In addition, a panel model, using only measures of owner-occupied housing debt and assets, is estimated using all five currently available waves. Evidence is presented to suggest that LFP is determined by several factors, including family structure, education, health and indebtedness. In general, most of the effect of indebtedness on an individualâs probability of participation in the labour force is captured through the household debt-servicing ratio, although the level of owner-occupied mortgage debt appears important for men. Also, the panel results suggest that accounting for unobserved heterogeneity across individuals is important when examining the influence of debt on labour supply.labour force participation; household debt; credit constraints; HILDA
Redshifted Absorption at He I 10830 as a Probe of the Accretion Geometry of T Tauri Stars
We probe the geometry of magnetospheric accretion in classical T Tauri stars
by modeling red absorption at He I 10830 via scattering of the stellar and
veiling continua. Under the assumptions that the accretion flow is an
azimuthally symmetric dipole and helium is sufficiently optically thick that
all incident 1-micron radiation is scattered, we illustrate the sensitivity of
He I 10830 red absorption to both the size of the magnetosphere and the filling
factor of the hot accretion shock. We compare model profiles to those observed
in 21 CTTS with subcontinuum redshifted absorption at He I 10830 and find that
about half of the stars have red absorptions and 1-micron veilings that are
consistent with dipole flows of moderate width with accretion shock filling
factors matching the size of the magnetospheric footpoints. However, the
remaining 50% of the profiles, with a combination of broad, deep absorption and
low 1-micron veiling, require very wide flows where magnetic footpoints are
distributed over 10-20% of the stellar surface but accretion shock filling
factors are < 1%. We model these profiles by invoking large magnetospheres
dilutely filled with accreting gas, leaving the disk over a range of radii in
many narrow "streamlets" that fill only a small fraction of the entire infall
region. In some cases accreting streamlets need to originate in the disk
between several stellar radii and at least the corotation radius. A few stars
have such deep absorption at velocities greater than half the stellar escape
velocity that flows near the star with less curvature than a dipole trajectory
seem to be required.Comment: 26 pages, emulateapj format, Accepted by ApJ, to appear 2008 November
1
Measurement of distortion product otoacoustic emissions in South African gold miners at risk for noise-induced hearing loss.
Background
The noise-exposed population in the mining industry in South Africa poses unique
problems to the occupational audiologist working in this environment, due to the
broad linguistic and cultural diversity in the audiology and mining environment.
Unfortunately, the problems are also exacerbated by a high incidence of
pseudohypacusis within this population who are incentivised by compensation for
NIHL. A solution to these specific problems would be the reliable and valid use of
an objective test of function such as the DPOAE. The rationale for the study
therefore was to extend the body of knowledge about the use of DPOAEs in the
noise-exposed mining population.
Methodology
The current study was divided into two phases: phase oneâs objectives entailed the
investigation of the characteristics of DPOAEs in a noise-exposed mining
population; phase two aimed to develop a multivariate regression model that would
facilitate the prediction of the hearing threshold levels from the DPOAE levels in
this population.
Objectives
The objectives in phase one of the study were to investigate the bivariate
correlations between DPOAE levels and air-conduction hearing threshold levels in
noise-exposed gold miners, for the three stimulus procedures. The study also
aimed to investigate the bivariate correlations between various pure-tone averages
(PTA) and the DPOAE averages of f2 frequencies closest to those pure-tone
frequencies. Similarly, the Speech Recognition Thresholds (SRT) were correlated
with DPOAE averages of f2 frequencies closest to the PTA.
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The study further aimed to investigate the characteristics of DPOAEs in noiseexposed
gold miners by comparing the average DPOAE levels for different age
category groups, different ethnic groups and for different occupation types. Finally,
phase one aimed to describe the characteristics of emission level and noise floor
differences (DP-NF) in a DPOAE database of a noise-exposed gold mining
population.
Phase two of the study had the objective of developing a multivariate prediction
model using stepwise regression analysis to identify which of the DPOAE
frequencies produced the best prediction of the audiogram frequencies when
multivariate inputs were used for each stimulus procedure. The objective was also
to evaluate the use of the predicted audiogramsâ calculated percentage loss of
hearing (PLH) with that of the actual PLH.
This retrospective record review used an audiological database from a mine in the
North West province of South Africa that contained 4800 records. The required
sample size to be representative of the population was statistically determined. The
records were randomly selected resulting a sample size for the FB2-S group of
161, for the FB1-S group of 177 and the FB1-S group of 155 respectively. The
hearing loss characteristics in the samples ranged from normal to profound losses
with the majority being mild to moderate hearing losses.
Results
The findings of phase one showed negative correlations ranging from -0.327 to
-0.573 for Frequency Band 1- Replicated (FB1-R) between DPOAE levels and air
conduction hearing threshold levels. Similarly, Frequency Band 1-Single (FB1-S)
and Frequency Band 2-Single (FB2-S) also showed negative correlations (ranging
from -0.203 to -0.609 and -0.274 to -0.738 respectively). These correlation
strengths have been confirmed previously by other published studies.
xxi
Correlations between groups of frequencies on an audiogram and averaged match
groups of DPOAE frequencies by intensity levels, both for PTA and SRT, ranged
between -0.323 and -0.661. No statistically significant differences were found
between the DPOAE measurements and ethnic groups of African and Caucasian
(Sample size of 175 for FB1-S, 137 for FB1-R and 161 for FB2-S). No differences
were found between the DPOAE levels and the occupation types of mining team
members, stopers and drillers. There was, however, a relational finding of a
progressive decrement of DPOAE intensity levels by decade of age increase
(Sample size of 37 for FB1-S, 45 for FB1-R and 155 for FB2-S).
Mean DP levels in this population ranged from 1.5 to -14 dB SPL, and mean NF
levels in the sample ranged from 0.1 to -16.8 dB SPL with the mean DP-NF
difference ranges form 0.4 to 9.3 dBSPL. More than 60% of the data collected
resulted in a DP-NF of less than 10 dB SPL.
The simple correlation relationship between hearing threshold levels and DPOAEs
did not sufficiently explain the variance within the sample and due to the fact that a
number of the independent variables in the sample were highly correlated, there
was a call to use a method that allows for multicolinearity (i.e. stepwise regression
analysis) in order to develop a prediction model. Consequently, phase two of the
study was able to compare actual air-conduction hearing threshold levels with
those calculated with the prediction model, and then calculate predicted
percentage loss of hearing (PLH) with actual PLH found in the noise-exposed gold
miners.
In phase two, with the use of the predictive models, the predicted hearing threshold
levels were found to differ from the actual thresholds by no more than 7dB HL
across all frequencies (average of 5 dB HL for FB1-R, 2 dB HL for FB1-S and 3 dB
HL for FB2-S). The differences for each audiogram frequency between the actual
and the predicted thresholds are represented on scatter plots in phase two of the
thesis. The PLH of the predicted audiograms was calculated using the weighted
xxii
tables prescribed by the Compensation for Occupational Diseases and Injuries Act
(COIDA). A comparison of the predicted PLH with the actual PLH indicated that the
predicted PLH ranged between minus 1.3% PLH and plus 6.7% PLH of the actual
PLH.
Results of the study are discussed with regards to the clinical implications, and the
implications for training occupational audiologists in South Africa. The results of
this study will improve and inform practice in the mining environment and in the
field of compensation for NIHL. By developing a reliable prediction tool which is
implemented on an objective test proven to document the extent of damage
incurred from noise-exposure, a clinician will gain greater confidence in an
accurate diagnosis, thereby further safeguarding a vulnerable population. The
results from this study are highly relevant to the mining industry and will add value
to the industrial development of South Africa by informing the policy on hearing
conservation and compensation, thereby increasing the awareness of the need for
improved occupational health and safety conditions and sustainable development
in the mining industry
The contribution of short-term memory capacity to reading ability in adolescents with cochlear implants
Increasing Capacity for Knowledge Translation: Understanding How Some Researchers Engage Policy-makers
The potential for research to influence policy, and for researchers to influence policy actors, is significant. The purpose of this qualitative study was to explore the experiences of health services researchers engaging in (or not able to engage in) policy-relevant research. Semi-structured telephone interviews were completed with 23 experienced researchers.The results paint a complex and dynamic picture of the policy environment and the relationship between government officials and academic researchers. Elements of this complexity included diverse understandings of the nature of policy and how research relates to policy; dealing with multiple stakeholders in the policy-making process; and identifying strategies to manage the different cultures of government and academia
F, G, K, M Spectral Standards in the Y Band (0.95-1.11 um)
We take advantage of good atmospheric transparency and the availability of
high quality instrumentation in the 1 um near-infrared atmospheric window to
present a grid of F, G, K, and M spectral standards observed at high spectral
resolution (R ~ 25,000). In addition to a spectral atlas, we present a catalog
of atomic line absorption features in the 0.95-1.11 um range. The catalog
includes a wide range of line excitation potentials, from 0-13 eV, arising from
neutral and singly ionized species, most frequently those of Fe I and Ti I at
low excitation, Cr I, Fe I, and Si I at moderate excitation, and C I, S I, and
Si I having relatively high excitation. The spectra also include several
prominent molecular bands from CN and FeH. For the atomic species, we analyze
trends in the excitation potential, line depth, and equivalent width across the
grid of spectroscopic standards to identify temperature and surface gravity
diagnostics near 1 um. We identify the line ratios that appear especially
useful for spectral typing as those involving Ti I and C I or S I, which are
temperature sensitive in opposite directions, and Sr II, which is gravity
sensitive at all spectral types. Ascii versions of all spectra are available to
download with the electronic version of the journal.Comment: 40 pages, 21 figures, 4 tables, spectra available for download with
source file, updated to mirror published versio
Probing T Tauri accretion and outflow with 1 micron spectroscopy
In a high-dispersion 1 ÎŒm survey of 39 classical T Tauri stars (CTTSs) veiling is detected in 80% of the stars, and He I λ10830 and PÎł line emission in 97%. On average, the 1 ÎŒm veiling exceeds the level expected from previously identified sources of excess emission, suggesting the presence of an additional contributor to accretion luminosity in the star-disk interface region. Strengths of both lines correlate with veiling, and at PÎł there is a systematic progression in profile morphology with veiling. He I λ10830 has an unprecedented sensitivity to inner winds, showing blueshifted absorption below the continuum in 71% of the CTTSs, compared to 0% at PÎł. This line is also sensitive to magnetospheric accretion flows, with redshifted absorption below the continuum found in 47% of the CTTSs, compared to 24% at PÎł. The blueshifted absorption at He I λ10830 shows considerable diversity in its breadth and penetration depth into the continuum, indicating that a range of inner wind conditions exist in accreting stars. We interpret the broadest and deepest blue absorptions as formed from scattering of the 1 ÎŒm continuum by outflowing gas whose full acceleration region envelopes the star, suggesting radial outflow from the star. In contrast, narrow blue absorption with a range of radial velocities more likely arises via scattering of the 1 ÎŒm continuum by a wind emerging from the inner disk. Both stellar and disk winds are accretion powered, since neither is seen in nonaccreting WTTSs and among the CTTSs helium strength correlates with veiling
Characteristics of noise-induced hearing loss in gold miners
The characteristics of Noise Induced Hearing Loss (NIHL) in gold miners of different ages and occupation types were examined and the incidence of tinnitus, vertigo/balance problems and nausea were determined. The results indicate that as a subject group these had symmetrical bilateral, mild hearing loss in the frequencies below 2000 Hz deteriorating to a moderate sloping hearing loss in the frequencies above 2000 Hz, and the loss did not demonstrate the expected ânotchâ at 4000 Hz that is usually found in NIHL. The average deterioration in the pure tone thresholds of gold miners was 3.5 dB at 500Hz; 2.75dB at 1000Hz, 15.37 dB at 2000Hz, 19.12 dB at 3000Hz; 20.87dB at 4000 Hz and 14.16dB at 6000 Hz for every ten years of age. The pattern of hearing loss varies for the different occupation types with machine operators being the most severely affected. The majority of tinnitus sufferers were in the age range 30-60 years and 57.8 % were in the under 60 years old category, while in the over 60 years the incidence was 4.8 %. The incidence of vertigo and nausea were found to be 27% in this population. The results of this study will equip the audiologist to better deal with diagnostic testing, successful hearing aid fitting and aural rehabilitation of this population. The study highlights the need for greater awareness and the imparting of detailed information to gold miners about the impact of noise on their hearing.Dissertation (MCommunication Pathology)--University of Pretoria, 2009.Speech-Language Pathology and Audiologyunrestricte
Ariel - Volume 2 Number 8
Editors
Richard J. Bonanno
Robin A. Edwards
Associate Editors
Steven Ager
Stephen Flynn
Shep Dickman
Tom Williams
Lay-out Editor
Eugenia Miller
Contributing Editors
Michael J. Blecker
Milton Packe
James J. Nocon
Lynne Porter
Editors Emeritus
Delvyn C. Case, Jr.
Paul M. Fernhof
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