Yunchen Huang

Driver behavior and accident frequency in school zones: Assessing the impact of sign saturation

Based on the models of human information processing, if a driver observes too many of the same signs, he or she may no longer pay attention to those signs. In the case of school zones, this expected effect may lead to non-compliance to posted speeds, negatively impacting safety around nearby schools. This study aims to investigate the effect of the number of nearby school zones on driver behavior (vehicle speed and compliance) and accident frequency. As a measure of the density of school zones, this study introduced and defined a new term sign saturation and presented a methodology to calculate sign saturation for school zones. Results found a significant effect of sign saturation on vehicle speed, compliance, and accident frequency. This study also examined the speeding behavior in school zones for different time of the day and day of the week. Results found that speeding was more prevalent in the early mornings and during the weekends.

The Effect of Design and Placement of Work-Zone Warning Signs on Driver Speed Compliance: A Simulator-Based Study

OCCUPATIONAL APPLICATIONS In this work, simulated driving was used to test how characteristics of dynamic message signs impact driver behavior when entering designated work zones. Driver compliance with posted speed limits was measured in response to signs that differed in terms of placement distance and type of sign design. Signs should be placed farther ahead of the work zone to enhance speed compliance. Such compliance can also be enhanced by using concise sign content. TECHNICAL ABSTRACT Background and Rationale: In recent years, the number of occupational fatalities occurring as a result of workers being struck by vehicles while on the job has remained high. Fatalities are especially apparent at road construction sites, where nearly half of the fatal occupational injuries were classified as a worker being struck by a moving vehicle, highlighting the need for research to identify techniques to reduce the incidence of injury in future years. Purpose: This project investigated how the characteristics of a dynamic message sign can impact driver compliance with posted information in work-zone settings, specifically signs indicating speed reduction. Methods: Driving simulation was used to assess the effects of three placement distances (305, 457, and 610 m before the work zone) and four sign designs (differing in whether the sign was static versus dynamic and the amount of information presented). The study was completed by 39 participants, during which driving speed and compliance with speed change were recorded. Results: Placement of the speed-reduction signs impacted driver behavior, with greater placement distances being associated with higher speed reduction and compliance rates. Speed reduction was also significantly impacted by sign design, with the largest speed reduction apparent with signs that are static or with dynamic signs that presented one complete statement per display frame. Conclusions: To achieve greater driver compliance with speed limits within work zones, greater sign placement distance is preferred. The content of dynamic message sign needs to be engineered to increase driver compliance by presenting direct, relevant information in concise and complete phrases.

Introducing a New Usability Framework for Analyzing Usability in a Multiple-device System

This paper fills in the theoretical gap in the existing usability evaluation literature by introducing a new usability framework: the Usability Paradigm for Multiple Device System (UPMDS). The traditional usability framework for single interface evaluation is not sufficient to analyze usability in multiple-device system, in which the interrelationship between the devices has an impact on user performance. Therefore, the transfer of learning paradigm was adopted. The UPMDS framework consists of two usability attributes: transferability and user perception, which were further decomposed into effectiveness, efficiency, and satisfaction, attractiveness. Three measurement types, behavioral cues, subjective ratings, and self reported results, were suggested to address the existing challenges in usability evaluation. Future research is suggested to utilize the concept of transfer of learning in the area of usability evaluation, and provide empirical validation to the current usability framework.

Training Effectiveness and Trainee Performance in a Voluntary Training Program Are Trainees Really Motivated

Effective training programs are critical for successful employee performance. The same can be said for volunteer programs. Volunteers need to have the knowledge and skills necessary to fulfill the mission of the organization. In this study, we examine the impact of training methods and trainees’ demographic factors on the effectiveness of a training program for a voluntary program. Survey results (N = 5,727) indicate a very low percentage of participation (16.46%) in the voluntary program after training. Responses also indicate that content knowledge recall after training is affected by training year (the year receiving training), industrial sector, calling history, and training delivery method. Participants’ desires for retraining are also impacted by the type of training received, the industry sector, as well as past participation in the program. Recommendations for voluntary training programs based on study results and future research directions are presented.

A System Transferability Questionnaire (STQ) Measuring Usability in a Multiple-Device System

The usability of a multiple device system largely depends on the ease of which users can transfer between using different devices. This paper is aimed at constructing a System Transferability Questionnaire (STQ) to effectively measure the subjective transferability of a multiple device system. Theoretical rationale and approach to develop the questionnaire were presented. A software usability study was conducted to test the STQ. Results showed that STQ helps to capture four factors regarding transferability, which are transfer experience (TE), overall experience (OE), consistency perception (CP) and functionality perception (FP). Users were more satisfied with OE (M=5.11 out of 7) and FP (M=5.20), as compared to TE (M=4.28) and CP (M=3.54), indicating redesign is necessary to improve the transferability of the two-software system.

Engaging Engineering Students With Transportation Safety

In this paper, we will introduce a newly created education module in transportation safety. The module is aimed at undergraduate engineering students, whose exposure to this topic is extremely limited, if they are exposed at all. Topics in the module include driver speed compliance, distracted driving, pedestrian safety, and vulnerable road users (VRUs) with an emphasis on young drivers. The module incorporates a number of items, including lecture material (both instructor and student versions), in-class activity, and laboratory exercises. The learning module is intended to supplement existing courses in engineering curricula. The goal of this learning module is to provide industrial engineering students with current research and knowledge in transportation safety. The module was recently piloted in an undergraduate Industrial Ergonomics courses. Results regarding the effectiveness of the module, as well as results on the student attainment of educational objectives, will be discussed.