An Energy-Harvesting Railroad Tie for Improving Track\ua0Condition Monitoring and Safety

Researchers at the Railway Technologies Laboratory (RTL) of the Center for Vehicle Systems and Safety (CVeSS) at Virginia Tech have designed and developed an energy harvesting railroad tie, shown in Figure 1, to power trackside electronics and sensors for improving track condition monitoring and safety. As a member of the Rail Transportation Engineering and Advance Maintenance (RailTEAM) consortium led by the University of Nevada Las Vegas (UNLV), RTL is funded by the U.S. Department of Transportation University Transportation Center program. RTL explores technologies that advance railroad sciences and enable the U.S. rail industry to become more efficient and globally competitive. The shortage of electrical power along railroad tracks significantly limits the railroads\u2019 ability to apply intelligent solutions for improving rail safety and connectivity. Much advanced wayside electrical equipment desired by the U.S. railroads cannot be employed readily on tracks due to the absence of electrical power. For example, some railroads use drones as a preferred means of physical inspection of track conditions, but the average maximum battery life for most commercial drones is only 22 to 27 minutes, significantly limit their operational range and length of flight

Validation of a multifactorial risk factor model used for predicting future caries risk with nevada adolescents

<p>Abstract</p> <p>Background</p> <p>The objective of this study was to measure the validity and reliability of a multifactorial Risk Factor Model developed for use in predicting future caries risk in Nevada adolescents in a public health setting.</p> <p>Methods</p> <p>This study examined retrospective data from an oral health surveillance initiative that screened over 51,000 students 13-18 years of age, attending public/private schools in Nevada across six academic years (2002/2003-2007/2008). The Risk Factor Model included ten demographic variables: exposure to fluoridation in the municipal water supply, environmental smoke exposure, race, age, locale (metropolitan vs. rural), tobacco use, Body Mass Index, insurance status, sex, and sealant application. Multiple regression was used in a previous study to establish which significantly contributed to caries risk. Follow-up logistic regression ascertained the weight of contribution and odds ratios of the ten variables. Researchers in this study computed sensitivity, specificity, positive predictive value (PVP), negative predictive value (PVN), and prevalence across all six years of screening to assess the validity of the Risk Factor Model.</p> <p>Results</p> <p>Subjects' overall mean caries prevalence across all six years was 66%. Average sensitivity across all six years was 79%; average specificity was 81%; average PVP was 89% and average PVN was 67%.</p> <p>Conclusions</p> <p>Overall, the Risk Factor Model provided a relatively constant, valid measure of caries that could be used in conjunction with a comprehensive risk assessment in population-based screenings by school nurses/nurse practitioners, health educators, and physicians to guide them in assessing potential future caries risk for use in prevention and referral practices.</p

Performance of Transportation Infrastructure During Kumamoto Earthquakes of April 14 and 16, 2016\u2014 A Reconnaissance Report

DTFH61-07-00031This report described a reconnaissance effort to document bridge performance during the Kumamoto earthquakes in Japan in April 2016. More than 180 bridges were damaged by these earthquakes. Of particular interest is the performance of bridges that were relatively new (15\u201320 yr old) or recently retrofitted. Damage sustained was significant and included bearing and shear key failures, distortion and local buckling of the steel superstructures, and foundation movement. Most of the damage could be attributed to extensive slope failures and intense shaking close to the causative fault. Recommendations for improving bridge performance in future earthquakes are given