Behavioral Analysis of Drivers Following Winter Maintenance Trucks Enabled with Collision Avoidance System

2019 ◽  
Vol 2673 (10) ◽  
pp. 394-404
Author(s):  
Rajat Verma ◽  
Ramin Saedi ◽  
Ali Zockaie ◽  
Timothy J. Gates
Keyword(s):  
Collision Avoidance ◽  
Traffic Safety ◽  
Response Times ◽  
Regression Tree ◽  
Field Testing ◽  
Operating Conditions ◽  
Classification And Regression Tree ◽  
Crash Risk ◽  
Winter Maintenance ◽  
Warning Light

Winter maintenance trucks (WMTs) often operate at lower speeds during inclement weather and roadway conditions, creating potential safety issues for motorists following close behind. In this study, a new prototype radar-based rear-end collision avoidance and mitigation system (CAMS) was tested to assess its impact on the behavior of drivers following WMTs. The system is designed to flash an auxiliary rear-facing warning light upon detection of a vehicle encroaching within an unsafe relative headway with the rear of the WMT. A series of field evaluations was performed during actual winter maintenance operations to assess the effectiveness of the system compared with normal operating conditions (i.e., without the CAMS warning light) toward improving driver behavior related to rear-end crash risk. Specifically, two measures were assessed: (a) rate of vehicles encroaching beyond a safe time headway threshold to the rear of the WMT, and (b) the reaction–response time of drivers. Classification and regression tree models were created for identifying the relevant factors influential in determining the change in driver response. The results indicate that this warning light was effective in reducing the likelihood of the subject drivers crossing beyond a relative headway of 4.5 s. It was also effective in reducing the reaction and response times of the drivers by 0.83 and 0.55 s (36% and 20% reduction), respectively. Although the results were encouraging, additional field testing is recommended before conclusions are drawn regarding the traffic safety impacts of the system.

Field Testing of Negative-Wave Leak Detection Systems

2014 ◽  
Author(s):  
Shane Siebenaler ◽  
Eric Tervo ◽  
Paul Vinh ◽  
Chris Lewis
Keyword(s):  
Response Times ◽  
Dynamic Pressure ◽  
User Interaction ◽  
Field Testing ◽  
Leak Detection ◽  
Operating Conditions ◽  
Negative Wave ◽  
Oil Pipeline ◽  
Detection Systems ◽  
The Cost

The pipeline industry is improving its ability to detect and locate leaks through emerging technologies. There has been a variety of research in recent years aimed at further development of sensor-based technologies for leak detection. A key obstacle to retrofitting existing pipelines with leak detection technologies is the cost and risk of installing hardware, particularly those sensors that require excavation near the pipe. There are many advantages to employing leak detection systems that can leverage existing instrumentation access locations. One such technology may be negative-wave leak detection systems. Negative-wave technologies work by measuring dynamic pressure changes in the pipe. It should be noted that some negative-wave systems require line modifications to accommodate multiple transmitters. While such systems have been on the market for many years, there is insufficient data available about their performance under various pipeline operating conditions for widespread adoption. In an effort to close many information gaps on the performance envelope of negative-wave technologies, a PRCI-funded field test was performed on a 41-kilometer segment of a 30-inch diameter heavy crude oil pipeline. Products from three suppliers were installed at either end of the test segment. Actual commodity withdrawals were conducted at a remote valve site approximately 21 kilometers into the segment during various operations to test the systems’ abilities to detect the withdrawals without direct user interaction. These test points included withdrawals during steady-state flowing, pump startup, and shutdown conditions. Data were collected from each system to determine their abilities to detect leaks under various conditions, abilities to locate the leak, false alarm rates, and response times. This test provided significant insight into the performance of such systems over the range of conditions tested. The key focus of this paper is the approach for conducting such multi-vendor commodity withdrawals. This project required some unique considerations for its execution. Such considerations are also documented to provide input to others who are considering such a test.

scholarly journals A Study on Re-Engagement and Stabilization Time on Take-Over Transition in a Highly Automated Driving System

Electronics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 344
Author(s):  
Hyunsuk Kim ◽  
Woojin Kim ◽  
Jungsook Kim ◽  
Seung-Jun Lee ◽  
Daesub Yoon ◽  
...  
Keyword(s):  
Human Factors ◽  
Response Times ◽  
Regression Tree ◽  
Classification And Regression Tree ◽  
Traffic Density ◽  
Automated Driving ◽  
Stabilization Time ◽  
Factors Affecting ◽  
Cart Analysis ◽  
Level 3

In the case of level 3 automated vehicles, in order to safely and quickly transfer control authority rights to manual driving, it is necessary that a study be conducted on the characteristics of human factors affecting the transition of manual driving. In this study, we conducted three experiments to compare the characteristics of human factors that influence the driver’s quality of response when re-engaging and stabilizing manual driving. The three experiments were conducted sequentially by dividing them into a normal driving situation, an obstacle occurrence situation in front, and an obstacle and congestion on surrounding roads. We performed a statistical analysis and classification and regression tree (CART) analysis using experimental data. We found that as the number of trials increased, there was a learning effect that shortened re-engagement times and increased the proportion of drivers with good response times. We found that the stabilization time increased as the experiment progressed, as obstacles appeared in front and traffic density increased in the surrounding lanes. The results of the analysis are useful for vehicle developers designing safer human–machine interfaces and for governments developing guidelines for automated driving systems.

Investigations of Road Wear Caused by Studded Tires

2014 ◽  
Vol 42 (1) ◽  
pp. 2-15
Author(s):  
Johannes Gültlinger ◽  
Frank Gauterin ◽  
Christian Brandau ◽  
Jan Schlittenhard ◽  
Burkhard Wies
Keyword(s):  
Traffic Safety ◽  
Test Bench ◽  
Operating Conditions ◽  
Test Method ◽  
Analytical Models ◽  
The Road ◽  
Driving Speed ◽  
Major Factors ◽  
Tire Friction ◽  
Variable Operating Conditions

ABSTRACT The use of studded tires has been a subject of controversy from the time they came into market. While studded tires contribute to traffic safety under severe winter conditions by increasing tire friction on icy roads, they also cause damage to the road surface when running on bare roads. Consequently, one of the main challenges in studded tire development is to reduce road wear while still ensuring a good grip on ice. Therefore, a research project was initiated to gain understanding about the mechanisms and influencing parameters involved in road wear by studded tires. A test method using the institute's internal drum test bench was developed. Furthermore, mechanisms causing road wear by studded tires were derived from basic analytical models. These mechanisms were used to identify the main parameters influencing road wear by studded tires. Using experimental results obtained with the test method developed, the expected influences were verified. Vehicle driving speed and stud mass were found to be major factors influencing road wear. This can be explained by the stud impact as a dominant mechanism. By means of the test method presented, quantified and comparable data for road wear caused by studded tires under controllable conditions can be obtained. The mechanisms allow predicting the influence of tire construction and variable operating conditions on road wear.

GCS-Pupil Score Has a Stronger Association with Mortality and Poor Functional Outcome than GCS Alone in Pediatric Severe Traumatic Brain Injury

2021 ◽  
pp. 1-8
Author(s):  
Binod Balakrishnan ◽  
Heather VanDongen-Trimmer ◽  
Irene Kim ◽  
Sheila J. Hanson ◽  
Liyun Zhang ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Functional Outcome ◽  
Cerebral Performance Category ◽  
Regression Tree ◽  
Classification And Regression Tree ◽  
Continuous Variables ◽  
Poor Functional Outcome ◽  
Severity Scores ◽  
Pupil Reactivity

<b><i>Background:</i></b> The Glasgow Coma Scale (GCS), used to classify the severity of traumatic brain injury (TBI), is associated with mortality and functional outcomes. However, GCS can be affected by sedation and neuromuscular blockade. GCS-Pupil (GCS-P) score, calculated as GCS minus Pupil Reactivity Score (PRS), was shown to better predict outcomes in a retrospective cohort of adult TBI patients. We evaluated the applicability of GCS-P to a large retrospective pediatric severe TBI (sTBI) cohort. <b><i>Methods:</i></b> Admissions to pediatric intensive care units in the Virtual Pediatric Systems (VPS, LLC) database from 2010 to 2015 with sTBI were included. We collected GCS, PRS (number of nonreactive pupils), cardiac arrest, abusive head trauma status, illness severity scores, pediatric cerebral performance category (PCPC) score, and mortality. GCS-P was calculated as GCS minus PRS. χ<sup>2</sup> or Fisher’s exact test and Mann-Whitney U test compared categorical and continuous variables, respectively. Classification and regression tree analysis identified thresholds of GCS-P and GCS along with other independent factors which were further examined using multivariable regression analysis to identify factors independently associated with mortality and unfavorable PCPC at PICU discharge. <b><i>Results:</i></b> Among the 2,682 patients included in the study, mortality was 23%, increasing from 4.7% for PRS = 0 to 80% for PRS = 2. GCS-P identified more severely injured patients with GCS-P scores 1 and 2 who had worse outcomes. GCS-P ≤ 2 had higher odds for mortality, OR = 68.4 (95% CI = 50.6–92.4) and unfavorable PCPC, OR = 17.3 (8.1, 37.0) compared to GCS ≤ 5. GCS-P ≤ 2 also had higher specificity and positive predictive value for both mortality and unfavorable PCPC compared to GCS ≤ 5. <b><i>Conclusions:</i></b> GCS-P, by incorporating pupil reactivity to GCS scoring, is more strongly associated with mortality and poor functional outcome at PICU discharge in children with sTBI.

scholarly journals Edible Insects: Preliminary Study about Perceptions, Attitudes, and Knowledge on a Sample of Portuguese Citizens

Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 709
Author(s):  
Sofia G. Florença ◽  
Paula M. R. Correia ◽  
Cristina A. Costa ◽  
Raquel P. F. Guiné
Keyword(s):  
Nutritive Value ◽  
Meat Products ◽  
Regression Tree ◽  
Good Alternative ◽  
Classification And Regression Tree ◽  
Categorical Variables ◽  
Final Conclusion ◽  
Edible Insects ◽  
Chi Square ◽  
Alternative Sources

This study investigated the knowledge, attitudes, consumption habits, and degree of acceptability of edible insects (EI) or derived products among Portuguese consumers. This work consisted of a questionnaire survey, undertaken on a sample of 213 participants. For the treatment of data, basic descriptive statistics were used, complemented with chi-square tests to assess some associations between categorical variables. Moreover, a tree classification analysis was carried out using a classification and regression tree (CRT) algorithm with cross-validation. The results indicated that people tend to have correct perceptions about the sustainability issues associated with the use of insects as alternative sources of protein; however, the level of knowledge and overall perception about their nutritive value is low. Regarding the consumption of EI, it was found that only a small part of the participants had already eaten them, doing it mostly abroad, by self-initiative, in a restaurant or at a party or event. Additionally, it was found that the reluctance to consume insects is higher if they are whole, but when they are transformed into ingredients used in food formulations, the level of acceptance increases. Furthermore, men have shown to have a better perception about EI, be more informed about sustainability, and have a higher level of acceptability when compared to women. As a final conclusion, it was observed that the Portuguese still show some resistance to adhere to the use of insects as replacements for meat products, but the market of insect based products can be a good alternative to overpass the neophobia associated with this type of food.

scholarly journals Validation and verification of predictive salivary biomarkers for oral health

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nagihan Bostanci ◽  
Konstantinos Mitsakakis ◽  
Beral Afacan ◽  
Kai Bao ◽  
Benita Johannsen ◽  
...  
Keyword(s):  
Oral Health ◽  
Predictive Accuracy ◽  
Statistical Tests ◽  
Area Under The Curve ◽  
Regression Tree ◽  
High Sensitivity ◽  
Oral Health Status ◽  
Classification And Regression Tree ◽  
Cart Analysis ◽  
Salivary Biomarkers

AbstractOral health is important not only due to the diseases emerging in the oral cavity but also due to the direct relation to systemic health. Thus, early and accurate characterization of the oral health status is of utmost importance. There are several salivary biomarkers as candidates for gingivitis and periodontitis, which are major oral health threats, affecting the gums. These need to be verified and validated for their potential use as differentiators of health, gingivitis and periodontitis status, before they are translated to chair-side for diagnostics and personalized monitoring. We aimed to measure 10 candidates using high sensitivity ELISAs in a well-controlled cohort of 127 individuals from three groups: periodontitis (60), gingivitis (31) and healthy (36). The statistical approaches included univariate statistical tests, receiver operating characteristic curves (ROC) with the corresponding Area Under the Curve (AUC) and Classification and Regression Tree (CART) analysis. The main outcomes were that the combination of multiple biomarker assays, rather than the use of single ones, can offer a predictive accuracy of > 90% for gingivitis versus health groups; and 100% for periodontitis versus health and periodontitis versus gingivitis groups. Furthermore, ratios of biomarkers MMP-8, MMP-9 and TIMP-1 were also proven to be powerful differentiating values compared to the single biomarkers.

scholarly journals Implications of Lifestyle and Occupational Factors on the Risk of Breast Cancer in Shiftwork Nurses

Healthcare ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 649
Author(s):  
Javier Fagundo-Rivera ◽  
Regina Allande-Cussó ◽  
Mónica Ortega-Moreno ◽  
Juan Jesús García-Iglesias ◽  
Adolfo Romero ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Shift Work ◽  
Regression Tree ◽  
Night Work ◽  
Circadian Disruption ◽  
Classification And Regression Tree ◽  
Baseline Risk ◽  
Unhealthy Lifestyle ◽  
Cross Sectional ◽  
Occupational Factors

Shift work that involves circadian disruption has been highlighted as a likely carcinogenic factor for breast cancer in humans. Also, unhealthy lifestyle habits observed in night work nurses could be causally related to an increase in the incidence of estrogen-positive breast tumours in this population. Assessing baseline risk of breast cancer in nurses is essential. The objective of this study was to analyze the risk of breast cancer that nurses had in relation to their lifestyle and labour factors related to shift work. A cross-sectional descriptive study through a questionnaire about sociodemographic variables, self-perception of health, and working life was designed. The sample consisted of 966 nurses. The relationship between variables was tested. A binary logistic regression and a classification and regression tree were performed. The most significant labour variables in relation to the risk of breast cancer were the number of years worked (more than 16 years; p < 0.01; OR = 8.733, 95% CI = 2.811, 27.134) and the total years performing more than 3 nights per month (10 or more years; p < 0.05; OR = 2.294, 95% CI = 1.008, 5.220). Also, the nights worked throughout life (over 500; OR = 4.190, 95% CI = 2.118, 8.287) were significant in the analysis. Nurses who had or ever had breast cancer valued their self-perceived health more negatively (p < 0.001) and referred a lower quality of sleep (p < 0.001) than the non-cases nurses. The occupational factors derived from night work could have several impacts on nurses’ health and their family-work balance. Promoting healthy lifestyles, informing about shift work risks, and adjusting shift work schedules are critical methods to decrease the possible effects of circadian disruption in nurses.

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