240 research outputs found
Product Market Competition and Human Resource Practices: An Analysis of the Retail Food Sector
The rise of super-centers and the entry of Wal-Mart into food retailing have dramatically altered the competitive environment in the industry. This paper explores the impact of such changes on the labor market practices of traditional food retailers. We use longitudinal data on workers and firms to construct new measures of compensation and employment, and examine how these measures evolve within and across firms in response to changes in product market structure. An additional feature of the analysis is to combine rich case study knowledge about the retail food industry with the new matched employer-employee data from the Census Bureau.
Zusammenhänge von Klimaanpassungsverhalten, (Risiko-)Wahrnehmung und Gesundheit unter Berücksichtigung geschlechtsspezifischer und sozioökonomischer sowie soziodemographischer Determinanten: eine Bevölkerungsumfrage in Leipzig
McCall T. Zusammenhänge von Klimaanpassungsverhalten, (Risiko-)Wahrnehmung und Gesundheit unter Berücksichtigung geschlechtsspezifischer und sozioökonomischer sowie soziodemographischer Determinanten: eine Bevölkerungsumfrage in Leipzig. Bielefeld: Universität Bielefeld; 2017
Examining the Gap: Compensation Disparities between Male and Female Physician Assistants.
BACKGROUND: Compensation disparities between men and women have been problematic for decades, and there is considerable evidence that the gap cannot be entirely explained by nongender factors. The current study examined the compensation gap in the physician assistant (PA) profession.
METHODS: Compensation data from 2014 was collected by the American Academy of PAs in 2015. Practice variables, including experience, specialty, and hours worked, were controlled for in an ordinary least-squares sequential regression model to examine whether there remained a disparity in total compensation. In addition, the absolute disparity in compensation was compared with historical data collected by American Academy of PAs over the previous 1.5 decades.
RESULTS: Without controlling for practice variables, a total compensation disparity of 9,695 remained between men and women (95% confidence interval, 10,952). A 17-year trend indicates the absolute disparity between men and women has not lessened, although the disparity as a percent of male compensation has decreased in recent years.
CONCLUSIONS: There remain challenges to ensuring pay equality in the PA profession. Even when compensation-relevant factors such as experience, hours worked, specialty, postgraduate training, region, and call are controlled for, there is still a substantial gender disparity in PA compensation. Remedies that may address this pay inequality include raising awareness of compensation disparities, teaching effective negotiation skills, assisting employers as they develop equitable compensation plans, having less reliance on past salary in position negotiation, and professional associations advocating for policies that support equal wages and opportunities, regardless of personal characteristics
Process-based modelling of storm impacts on gravel coasts
Full version unavailable due to 3rd party copyright restrictions.Gravel beaches and barriers occur on many high-latitude, wave-dominated coasts
across the world. Due to their natural ability to dissipate large amounts of wave
energy, gravel coasts are widely regarded as an effective and sustainable form of
coastal defence. However, during extreme events waves may overtop, overwash, and
even lower, the crest of the gravel beach, flooding the hinterland. In the evaluation
of the safety of gravel coasts against flooding, coastal managers currently rely on
models that have been shown in previous studies to be inaccurate. The research in
this thesis attempts to improve the current predictive capacity of gravel beach storm
response by developing a new process-based model to simulate storm impacts on
gravel coasts.
The numerical model developed in this thesis, called XBeach-G, is a morphodynamic, depth-averaged, cross-shore profile model, based on the XBeach model for
sandy coasts (Roelvink et al., 2009). The model simulates the morphological response of gravel beaches and barriers to storms by solving: (1) intra-wave flow and
surface elevation variations using a non-hydrostatic extension of the non-linear shallow water equations; (2) groundwater processes, including infiltration and exfiltration, using a Darcy-Forchheimer-type model; and (3) bed load transport of gravel using a modification of the Van Rijn (2007a) bed load transport equation to include flow
acceleration effects, which are shown to be significant on coarse-grained beaches.
The model is extensively validated for hydrodynamics, groundwater dynamics and
morphodynamics using detailed data collected in physical model experiments, as
well as data collected in the field on four natural gravel beaches in the UK and one
in France.
Validation results show that the model has high quantitative skill in simulating observed hydrodynamics on gravel beaches across a wide range of forcing conditions,
in particular with regard to wave transformation, wave run-up and wave overtopping.
Spatial and temporal variations in groundwater head are shown to be well represented
in the model through comparison to data recorded in a physical model experiment.
Validation of the morphodynamic component of XBeach-G shows that the model
has high model skill (median BSS 0.75) in simulating storm impacts on five gravel
beaches during ten storm events, with observed morphodynamic response ranging
from berm-building to barrier rollover.
The model is used to investigate hydrodynamic processes on gravel beaches during
storms, where it is found that incident-band variance is elemental in the generation
of wave run-up on gravel beaches. Furthermore, simulations of wave run-up during high-energy wave events show a distinct disparity between run-up predicted by
empirical relations based on the Iribarren parameter and wave steepness, and run-up
predicted by XBeach-G, where predictions by the empirical relations substantially
underestimate observed wave run-up.
Groundwater processes are shown, by means of sensitivity simulations, to strongly
affect the morphodynamic response of gravel beaches and barriers to storms. The
research in this thesis supports the hypothesis that infiltration in the swash is a key
driver for the berm-building response of gravel beaches and helps to reduce erosion
of the upper beach during storms. Through model simulations on a schematic gravel
barrier it is shown that groundwater processes effectively increases the capacity of
gravel barriers to withstand storms with 1-3 m higher surge levels than if groundwater processes did not occur. Reducing the width of a barrier leads to a lowering of
this capacity, thereby reducing the resilience of the barrier to extreme storm events.
Despite its strong influence on gravel beach morphodynamics, it is found that infiltration plays a relatively small role on wave run-up levels on most natural gravel
beaches (median R 2% run-up level reduction of 8%).
Application of the model in validation simulations and sensitivity simulations in this
thesis, as well as in storm hindcast simulations discussed by McCall et al. (2013)
shows the value of using the process-based XBeach-G model in coastal flooding
analysis over the use of empirical tools. While no model can be considered entirely
accurate, application of XBeach-G in all hindcast overwash simulations has lead to
reasonable estimates of overtopping discharge and of morphological change, which
is a significant improvement over the frequently substantial errors of the empirical
tool designed for this purpose.EPSR
Product Market Competition and Human Resource Practices: An Analysis of the Retail Food Sector
The rise of super-centers and the entry of Wal-Mart into food retailing have dramatically altered the competitive environment in the industry. This paper explores the impact of such changes on the labor market practices of traditional food retailers. We use longitudinal data on workers and firms to construct new measures of compensation and employment, and examine how these measures evolve within and across firms in response to changes in product market structure. An additional feature of the analysis is to combine rich case study knowledge about the retail food industry with the new matched employer-employee data from the Census Bureau.supermarkets, human resource practices, competition, internal labor market, wage growth, Labor and Human Capital, Marketing,
Design and Construction of a Chemical Engineering (ChemE) Car Using Thermoelectrics
Six chemical engineering undergraduates at the University of South Carolina formed a team to compete in the 2014 AIChE Chem-E-Car competition at the Southern Regional Student Conference in San Juan, Puerto Rico, in March. In the Chem-E-Car competition, students must design and build a vehicle powered by an unconventional form of chemical energy to carry a specified weight over a given distance (1). The group used knowledge gained through undergraduate study to construct a small-scale vehicle that is powered by a set of thermoelectric generators utilizing a heat gradient between boiling water and an ethanol-dry ice mixture (2). An iodine clock reaction is used in conjunction with photoresistors and an Arduino microcontroller to stop the car after the reaction goes to completion. The group had a successful run at the regional competition in Puerto Rico, earning first place in the research poster competition and fourth place in the performance competition. The group was selected as one of five teams to advance to the national competition held at the AIChE Annual Meeting in November 2014 in Atlanta, Georgia
A new parameterisation for runup on gravel beaches
publisher: Elsevier articletitle: A new parameterisation for runup on gravel beaches journaltitle: Coastal Engineering articlelink: http://dx.doi.org/10.1016/j.coastaleng.2016.08.003 content_type: article copyright: © 2016 The Authors. Published by Elsevier B.V. Open Access funded by Engineering and Physical Sciences Research Counci
Supermarket Human Resource Practices and Competition from Mass Merchandisers
The rise of supercenters and the entry of Wal-Mart into food retailing have dramatically altered the competitive
environment in the industry. This paper explores the impact of such changes on the labor market practices of traditional
food retailers. We use longitudinal data on workers and firms to construct new measures of compensation and employment,
and examine how these measures evolve within and across firms in response to changes in product market competition. An
additional feature of the analysis is to combine rich case study knowledge about the retail food industry with the new
matched employer-employee data from the Census Bureau. We compare a set of human resource practices using measures
based on the matched employer-employee data to an index based on survey data and case studies. The consistency between
the two approaches suggests that the measures are capturing important differences in supermarket human resource practices
and policies. Analysis of administrative data combined with case study observations strengthens our understanding of the
diversity of human resource practices in the retail food industry
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