Assessing the Runoff Reduction Potential of Highway Swales and WinSLAMM as a Predictive Tool

Across the United States, the impacts of stormwater runoff are being managed through the National Pollutant Discharge Elimination System (NPDES) in an effort to restore and/or maintain the quality of surface waters. State transportation authorities fall within this regulatory framework, being tasked with managing runoff leaving their impervious surfaces. Opportunely, the highway environment also has substantial amounts of green space that may be leveraged for this purpose. However, there are questions as to how much runoff reduction is provided by these spaces, a question that may have a dramatic impact on stormwater management strategies across the country. A highway median swale, located on Asheville Highway, Knoxville, Tennessee, was monitored for hydrology over an 11-month period. The total catchment was 0.64 ha, with 0.26 ha of roadway draining to 0.38 ha of a vegetated median. The results of this study indicated that 87.2% of runoff volume was sequestered by the swale. The Source Loading and Management Model for Windows (WinSLAMM) was used to model the swale runoff reduction performance to determine how well this model may perform in such an application. To calibrate the model, adjustments were made to measured on-site infiltration rates, which was identified as a sensitive parameter in the model that also had substantial measurement uncertainty in the field. The calibrated model performed reasonably with a Nash Sutcliffe Efficiency of 0.46. WinSLAMM proved to be a beneficial resource to assess green space performance; however, the sensitivity of the infiltration parameter suggests that field measurements of this characteristic may be needed to achieve accurate results.

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Hospital downsizing and workforce reduction strategies: some inner workings

Health Services Management Research ◽

10.1258/095148403762539103 ◽

2003 ◽

Vol 16 (1) ◽

pp. 13-23 ◽

Cited By ~ 13

Author(s):

Thomas P. Weil

Keyword(s):

Economies Of Scale ◽

Management Strategies ◽

The United States ◽

Direct Patient Care ◽

Workforce Reduction ◽

Minimal Impact ◽

Physician Practices ◽

Reduction Strategies ◽

Managerial Strategies

Downsizing, manpower reductions, re-engineering, and resizing are used extensively in the United States to reduce cost and to evaluate the effectiveness and efficiency of various functions and processes. Published studies report that these managerial strategies result in a minimal impact on access to services, quality of care, and the ability to reduce costs. But, these approaches certainly alienate employees. These findings are usually explained by the significant difficulties experienced in eliminating nursing and other similar direct patient care-oriented positions and in terminating white-collar employees. Possibly an equally plausible reason why hospitals and physician practices react so poorly to these management strategies is their cost structure-high fixed (85%) and low variable (15%)-and that simply generating greater volume does not necessarily achieve economies of scale. More workable alternatives for health executives to effectuate cost reductions consist of simplifying prepayment, decreasing the overall availability and centralizing tertiary services at academic health centres, and closing superfluous hospitals and other health facilities. America's pluralistic values and these proposals having serious political repercussions for health executives and elected officials often present serious barriers in their implementation.

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Application of an Analytic Methodology to Estimate the Movements of Moored Vessels Based on Forecast Data

Water ◽

10.3390/w11091841 ◽

2019 ◽

Vol 11 (9) ◽

pp. 1841 ◽

Cited By ~ 2

Author(s):

Sande ◽

Figuero ◽

Tarrío-Saavedra ◽

Peña ◽

Alvarellos ◽

...

Keyword(s):

Mean Absolute Error ◽

Field Measurements ◽

Absolute Error ◽

Coefficient Of Determination ◽

Predictive Tool ◽

Analytical Methodology ◽

Port Management ◽

Operational Conditions ◽

Forecast Data

A port’s operating capacity and the economic performance of its concessions are intimately related to the quality of its operational conditions. This paper presents an analytical methodology for estimating the movements of a moored vessel based on field measurements and forecast data, specifically including ship dimensions and meteorological and maritime conditions. The methodology was tested and validated in the Outer Port of Punta Langosteira, A Coruña, Spain. It was determined that the significant wave height outside the port, and the ratio of the vessel’s length divided by its beam (L/B), are the variables that most influence movements. Furthermore, heave and surge are the movements with a better value of the coefficient of determination (R2 values of 0.71 and 0.67, respectively), the sway (R2 = 0.30) and roll (R2 = 0.27) being the worst when using the available forecast variables of the Outer Port of Punta Langosteira. Despite their low R2 values, sway and roll models are able to estimate the main trends of these movements. The obtained estimators provide good predictions with assumable error values (root mean square error—RMSE and mean absolute error—MAE), showing their potential application as a predictive tool. Finally, as a consequence, the A Coruña Port Authority has included the results of the methodology in its port management system allowing them to predict moored vessel behavior in the port.

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