The treatment of early onset scoliosis using surgical growing rods suffers from high failure rate. Fatigue resistance can be improved by inducing compressive residual stresses within the near surface region. An in-depth investigation of the residual stresses profile evolution is performed through the sequence of material processing steps followed by surgeons handling operations, in connection to material properties.
View Article and Find Full Text PDFThis study investigates the use of ultra-wideband (UWB) tags in traffic conflict techniques (TCT) for the estimation of time occupancy in a real-world setting. This study describes UWB technology and its application in the TCT framework. Many experiments were conducted to evaluate the accuracy of the occupancy time measurement using a UWB-based tag.
View Article and Find Full Text PDFSensors (Basel)
April 2023
Pedestrian safety has been evaluated based on the mean number of pedestrian-involved collisions. Traffic conflicts have been used as a data source to supplement collision data because of their higher frequency and lower damage. Currently, the main source of traffic conflict observation is through video cameras that can efficiently gather rich data but can be limited by weather and lighting conditions.
View Article and Find Full Text PDFAccid Anal Prev
February 2023
Musculoskeletal modeling is commonly used to simulate and compare various movements between individuals. For conditions such as femoroacetabular impingement syndrome (FAIS), individuals tend to walk with more anterior pelvic tilt than those without FAIS. However, it is unknown whether accounting for pelvic tilt in musculoskeletal modeling would lead to a change in muscle forces and in turn, joint forces.
View Article and Find Full Text PDFJ Mech Behav Biomed Mater
September 2021
The widely used treatment of early onset scoliosis based on fusionless spinal instrumentation with growing rods suffers from severe complications due to premature rod failure. Only few studies have explored the fracture mechanisms in single rod constructs, while clinical practice urgently needs guidance. The objectives of this study are (i) to determine the failure mechanisms in Ti-6Al-4V alloy, Ti Cp 2 and Co-Cr alloy rods, and (ii) to propose strategies to reduce the risk of rod fracture.
View Article and Find Full Text PDFSurrogate safety measures have been advocated as a complementary approach to study safety from a broader perspective than relying on crash data alone. This study proposes an approach to incorporate different surrogate safety measures in a unified framework for road safety estimation within the bivariate extreme value theory framework. The model structure, model specification, threshold selection method, and parameter estimation method of the bivariate threshold excess model are introduced.
View Article and Find Full Text PDFLeft-turn lanes are commonly introduced to provide space to accommodate comfortable deceleration and adequate storage of turning vehicles. Operational shortcomings may arise due to inadequate length, including overflow and blockage of left-turn entrance by queues on an adjacent through lane. This study investigates the potential safety and operational benefits of treating left-turn lanes by extending the length further upstream a signalized intersection.
View Article and Find Full Text PDFThis paper studies the relevant factors in mixed urban traffic that may impact the lateral spacing between bicycles and vehicles (passing distance, PD), and their resulting effect on a bicyclists' comfort based on a study of six sites in Ottawa, Canada. The observations are: [i] the average position of bicycles from the curb is 0.57m, and lesser (i.
View Article and Find Full Text PDFTraffic conflict indicators measure the temporal and spatial proximity of conflict-involved road users. These indicators can reflect the severity of traffic conflicts to a reliable extent. Instead of using the indicator value directly as a severity index, many link functions have been developed to map the conflict indicator to a severity index.
View Article and Find Full Text PDFObjective: During menopause, women often experience some symptoms which may affect their daily activities. Information about menopausal experiences among different racial and ethnic groups is important for healthcare personnel to provide appropriate and specific interventions. The aim of the present study was thus to determine the frequency and determinants of severity of menopausal symptoms among Egyptian women using the Menopause Rating Scale as a screening tool for identification of menopausal symptoms.
View Article and Find Full Text PDFAccid Anal Prev
January 2014
The validity of traffic conflicts and other surrogate events has been a great concern in the development and application of surrogate safety measures. Extreme value theory (EVT) offers a strong modeling framework for linking surrogate measures of safety to crash frequency. This study aims at developing, validating, and comparing two EVT modeling approaches for characterizing extreme events.
View Article and Find Full Text PDFSeveral earlier studies have noted the shortcomings with existing geometric design guides which provide deterministic standards. In these standards the safety margin of the design output is generally unknown and there is little knowledge of the safety implications of deviating from the standards. To mitigate these shortcomings, probabilistic geometric design has been advocated where reliability analysis can be used to account for the uncertainty in the design parameters and to provide a mechanism for risk measurement to evaluate the safety impact of deviations from design standards.
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