Woodhouse I.H.,University of Edinburgh |
Cottin A.,MS |
Cottin A.,U.S. Army
GIM International | Year: 2015
Until now, most commercially available airborne Lidar systems have operated on one single wavelength, reflecting energy from a pulse which is then used for classification or visualisation. New developments have produced the first multispectral Lidar systems, which scan using laser pulses in a number of different wavelengths. Multispectral Lidar data contains valuable information about the objects scanned. The fast-moving advancements in this field are likely to represent the next technological leap in Lidar systems.
ICCTP 2010: Integrated Transportation Systems: Green, Intelligent, Reliable - Proceedings of the 10th International Conference of Chinese Transportation Professionals | Year: 2010
A High Occupancy Vehicle (HOV) lane is typically a retrofitted lane next to the median along urban freeways that is dedicated to high occupancy vehicles with more than one passenger. Due to right-of-way constraints, median barrier and bridge piers may become sight constraints when freeways curve to the left (relative to the direction of travel), so that stopping sight distance would not be satisfied. On the other hand, since an HOV lane is supposed to be operating at a higher level of service than the neighboring mixed-flow lanes, sight constraints may also come from the queued vehicles in the adjacent congested mixed-flow lanes when freeways curve to the right. It is the focus of this paper to demonstrate and evaluate these sight distance constraints and to recommend countermeasures to alleviate or eliminate their impacts, either by reducing design speed, altering horizontal and cross-sectional design, or both. © 2010 ASCE.
Wilson D.J.,Imperial College London |
Crocket K.C.,Imperial College London |
Crocket K.C.,Scottish Association for Marine Science |
Van De Flierdt T.,Imperial College London |
And 3 more authors.
Paleoceanography | Year: 2014
The last deglaciation was characterized by a series of millennial-scale climate events that have been linked to deep ocean variability. While often implied in interpretations, few direct constraints exist on circulation changes at mid-depths. Here we provide new constraints on the variability of deglacial mid-depth circulation using combined radiocarbon and neodymium isotopes in 24 North Atlantic deep-sea corals. Their aragonite skeletons have been dated by uranium-series, providing absolute ages and the resolution to record centennial-scale changes, while transects spanning the lifetime of a single coral allow subcentennial tracer reconstruction. Our results reveal that rapid fluctuations of water mass sourcing and radiocarbon affected the mid-depth water column (1.7-2.5 km) on timescales of less than 100 years during the latter half of Heinrich Stadial 1. The neodymium isotopic variability (-14.5 to -11.0) ranges from the composition of the modern northern-sourced waters towards more radiogenic compositions, suggesting the presence of a greater southern-sourced component at some times. However, in detail, simple two-component mixing between well-ventilated northern-sourced and radiocarbon-depleted southern-sourced water masses cannot explain all our data. Instead, corals from ∼15.0 ka and ∼15.8 ka may record variability between southern-sourced intermediate waters and radiocarbon-depleted northern-sourced waters, unless there was a major shift in the neodymium isotopic composition of the northern end-member. In order to explain the rapid shift towards the most depleted radiocarbon values at ∼15.4 ka, we suggest a different mixing scenario involving either radiocarbon-depleted deep water from the Greenland-Iceland-Norwegian Seas or a southern-sourced deep water mass. Since these mid-depth changes preceded the Bolling-Allerod warming and were apparently unaccompanied by changes in the deep Atlantic, they may indicate an important role for the intermediate ocean in the early deglacial climate evolution. ©2014. American Geophysical Union. All Rights Reserved.
Brown L.G.,Centers for Disease Control and Prevention |
Khargonekar S.,Centers for Disease Control and Prevention |
Journal of Food Protection | Year: 2013
This study was conducted by the Environmental Health Specialists Network (EHS-Net) of the Centers for Disease Control and Prevention. The purpose was to examine restaurant chicken preparation and cooking practices and kitchen managers' food safety knowledge concerning chicken. EHS-Net members interviewed managers about chicken preparation practices in 448 restaurants. The study revealed that many restaurants were not following U.S. Food and Drug Administration Food Code guidance concerning cross-contamination prevention and proper cooking and that managers lacked basic food safety knowledge about chicken. Forty percent of managers said that they never, rarely, or only sometimes designated certain cutting boards for raw meat (including chicken). One-third of managers said that they did not wash and rinse surfaces before sanitizing them. Over half of managers said that thermometers were not used to determine the final cook temperature of chicken. Only 43% of managers knew the temperature to which raw chicken needed to be cooked for it to be safe to eat. These findings indicate that restaurant chicken preparation and cooking practices and manager food safety knowledge need improvement. Findings from this study could be used by food safety programs and the restaurant industry to target training and intervention efforts to improve chicken preparation and cooking practices and knowledge concerning safe chicken preparation.
Yang G.,University of Nevada, Reno |
Tian Z.,University of Nevada, Reno |
Xu H.,University of Nevada, Reno |
Transportation Research Record | Year: 2016
AASHTO's A Policy on Geometric Design of Highways and Streets (Green Book) is currently used by most state departments of transportation in the United States in determining the design length of acceleration lanes of metered on-ramps; however, the recommended acceleration lengths have not been updated for several decades. This study aimed to develop a method for determining acceleration lengths at metered on-ramps. Vehicle location versus time information was collected via parallel cameras at seven metered on-ramps in California; then, a piecewise constant acceleration model was proposed to calculate the spot speeds of individual samples at predetermined locations. The percentile distanceversus-speed profiles at each ramp were built, and regression models were generated to predict the required acceleration length at a given merge speed. The 85th percentile data were recommended as the minimum acceleration length to accommodate most drivers in accelerating to a safe merging speed. The new recommendation was compared with the existing guidance in the Green Book. On the basis of 1, 658 individual samples, it was found that the recommended acceleration lengths were shorter than the Green Book guidelines by 10% to 35%. Also, results showed that acceleration lengths for tractor trailer trucks were approximately 60% greater than the Green Book guidelines.