Faculty Research Publications (Civil and Construction Engineering)

Heart Motion Prediction in Robotic- Assisted Beating Heart Surgery: A Nonlinear Fast Adaptive Approach

2013-01-31T00:00:00Z

Heart Motion Prediction in Robotic- Assisted Beating Heart Surgery: A Nonlinear Fast Adaptive Approach Liang, Fan; Yu, Yang; Wang, Haizhong; Meng, Xiaofeng Off-pump Coronary Artery Bypass Graft (CABG) surgery outperforms traditional on-pump surgery because the assisted robotic tools can alleviate the relative motion between the beating heart and robotic tools. Therefore, it is possible for the surgeon to operate on the beating heart and thus lessens post surgery complications for the patients. Due to the highly irregular and non-stationary nature of heart motion, it is critical that the beating heart motion is predicted in the model-based track control procedures. It is technically preferable to model heart motion in a nonlinear way because the characteristic analysis of 3D heart motion data through Bi-spectral analysis and Fourier methods demonstrates the involved nonlinearity of heart motion. We propose an adaptive nonlinear heart motion model based on the Volterra Series in this paper. We also design a fast lattice structure to achieve computational-efficiency for real-time online predictions. We argue that the quadratic term of the Volterra Series can improve the prediction accuracy by covering sharp change points and including the motion with sufficient detail. The experiment results indicate that the adaptive nonlinear heart motion prediction algorithm outperforms the autoregressive (AR) and the time-varying Fourier-series models in terms of the root mean square of the prediction error and the prediction error in extreme cases. This is the publisher’s final pdf. The published article is copyrighted by InTech — Open Access Company and can be found at: http://www.intechopen.com/.

A high-resolution study of tides in the Delaware Bay: Past conditions and future scenarios

2013-01-31T00:00:00Z

A high-resolution study of tides in the Delaware Bay: Past conditions and future scenarios Hall, George F.; Hill, David F.; Horton, Benjamin P.; Engelhart, Simon E.; Peltier, W. R. Tides in the Delaware Bay (USA) have been modeled from 7000 years before present (7 ka) to the present day and for selected future sea-level rise scenarios (100 years, 300 years). Historic bathymetries were constructed through use of glacial isostatic adjustment models and a very high spatial resolution (< 100 m) was used at the shoreline. Future bathymetries were obtained by extrapolating these glacial isostatic adjustment models and applying an additional eustatic sea-level rise. It was found that tides in the lower bay have remained fairly constant through time but that tides in the upper bay have increased steadily from about 4 ka to the present day; a nearly 100% increase in total. The future runs demonstrated spatially complex behavior with tidal-range changes of up to 10%. Citation: Hall, G. F., D. F. Hill, B. P. Horton, S. E. Engelhart, and W. R. Peltier (2013), A high-resolution study of tides in the Delaware Bay: Past conditions and future scenarios, Geophys. Res. Lett., 40, 338-242, doi:10.1029/2012GL054675. The article is copyrighted by American Geophysical Union and published by Wiley-Blackwell and can be found at: http://onlinelibrary.wiley.com/.

Spatial identification and optimization of upland wetlands in agricultural watersheds

2013-01-24T00:00:00Z

Spatial identification and optimization of upland wetlands in agricultural watersheds Babbar-Sebens, Meghna; Barr, Robert C.; Tedesco, Lenore P.; Anderson, Milo Wetland ecosystems are considered as potential ecological solutions for increasing the capacity of watersheds to store runoff waters upstream, and thereby, decrease risk of downstream flooding. Especially in tile-drained agricultural landscapes, wetlands constructed to intercept these tiles can serve as storage basins for agricultural runoff, leading to both reduction in peak runoff flows and diminished transport of agricultural nutrients. The objective of this study was to develop a watershed-scale methodology for identifying potential sites for wetlands in a tile-drained landscape in the Midwestern USA, and for optimizing the spatial distribution of these wetlands for reductions in peak runoff flows. The benefits of this methodology is demonstrated by using it for selecting appropriate wetland restoration and/or creation sites in Eagle Creek Watershed (ECW), located 10 miles northwest of Indianapolis, IN, USA. Results show that a large number of potential sites could be identified (e.g., 2953 sites in ECW), and with a choice of effective wetland design parameters and with spatial optimization of their areas, locations, and drainage areas, it is possible to achieve significant peak flow reductions with fewer sites and smaller wetlands. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.elsevier.com/.

Planning of a Secondary Road Network for Low-Speed Vehicles in Small or Medium-Sized City: Using Google Earth

2012-01-01T00:00:00Z

Planning of a Secondary Road Network for Low-Speed Vehicles in Small or Medium-Sized City: Using Google Earth Jannat, Mafruhatul; Hunter-Zaworski, Katharine M. In response to the growing environmental concern, the use of low speed vehicles (LSVs) on public roadways is gradually increasing in recent years as a short-range alternative to fossil-fueled autos. Primarily designed for protected environments and gated communities, LSVs have a maximum speed limit of 25 mph and are not subjected to the same Federal Motor Vehicle Safety Standards required for regular passenger cars. This paper presents a comprehensive planning methodology for the development of a secondary low speed roadway network primarily intended for use by LSVs that can be applied to small or medium-sized cities with closely located activity spaces. Typically, small or medium sized cities have limited planning or construction resources, therefore the objective was to develop the low speed network based on the existing road system of the city, with minimal infrastructure modifications. The City’s Transportation Plan and public opinion on route preference were integrated with the road analysis tool of Google Earth to accomplish the network development process. Public involvement in the process through a survey provided valuable insight on users’ route choice behavior; whereas the roadway inventory by City’s Transportation Planning document and Google Earth helped to evaluate city’s actual transportation infrastructure and also helped to analyze the factors influencing LSV users’ route preference behavior. The developed low speed roadway network is expected to provide safe and efficient connectivity from neighborhood areas to major activity centers of the city by LSVs, while minimally affecting the safe operations of regular automobiles. This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Transportation Research Board of the National Academies and can be found at: http://www.trb.org/Main/Blurbs/154702.aspx.