Ken-Yu Lin

An evaluation of wearable sensors and their placements for analyzing construction worker's trunk posture in laboratory conditions

This study investigates the effect of sensor placement on the analysis of trunk posture for construction activities using two off-the-shelf systems. Experiments were performed using a single-parameter monitoring wearable sensor (SPMWS), the ActiGraph GT9X Link, which was worn at six locations on the body, and a multi-parameter monitoring wearable sensor (MPMWS), the Zephyr BioHarness™3, which was worn at two body positions. One healthy male was recruited and conducted 10 experiment sessions to repeat measurements of trunk posture within our study. Measurements of upper-body thoracic bending posture during the lifting and lowering of raised deck materials in a laboratory setting were compared against video-captured observations of posture. The measurements from the two sensors were found to be in agreement during slow-motion symmetric bending activities with a target bending of ≤45°. However, for asymmetric bending tasks, when the SPMWS was placed on the chest, its readings were substantially different from those of the MPMWS worn on the chest or under the armpit.

Serious Games for the Learning and Practices of Hazard Recognition: Understanding the Design Complexity for 3D Construction Site Modeling

Among the various construction safety and health (S&H) training methods, 3D digital game-based learning is believed to have a great potential. This method can combine various educational strategies to engage learners that have grown up with computer gaming. To this end, an increasing number of 3D serious games have been developed for the learning of construction S&H. However, developing a virtual construction-site simulation for serious gaming is a tedious process. Little has been done to understand the simulation parameters that should be controlled in order to adequately represent the dynamics of a construction site and, as a result, to influence student learning. Therefore, the purpose of this study is to understand and prioritize the 3D construction-site simulation parameters for learning hazard recognition. In the paper, the researchers reported their findings on the S&H game design framework as an initial step to identify how simulation parameters such as texture, lighting, and animation could align with game contents and positively affect student learning. A future experiment for validating each parameter was also introduced. The researchers expect that the final research outcomes will enable construction education stakeholders to better understand and manage the design complexity of 3D construction-site modeling for S&H serious games.

Quantifying the Impacts of Failures of Departments of Transportation Building Systems on Road System Users

Because of the financial crisis of 2007 to 2008 and the subsequent economic downturn, funding for transportation agencies has been consistently reduced. This lack of funds prevents the building assets of transportation agencies from being efficiently maintained, so failures may occur that discontinue employees’ operations and activities and affect transportation system users. Thus, to maximize the use of available funding, it is compelling to create innovative tools and techniques capable of estimating how potential failures can affect employees’ activities and, eventually, transportation system users. Facility managers and decision makers could use such estimates to make decisions on maintenance of building assets that would minimize the risks of disruptions to employees and transportation system users. Among the capital assets of the Washington State Department of Transportation (DOT), transportation equipment fund (TEF) shops are crucial in ensuring timely and effective care and maintenance of the majority of state vehicles and equipment. Therefore, any disruption of the operations of TEF shop facilities could significantly affect not only the Washington State DOTs vehicles and equipment maintenance but also the departments ability to fulfill its core mission. Given the importance of TEF shops, this exploratory case study investigates the failures that have occurred or are likely to occur in these facilities and employs discrete-event simulation to quantify the consequences of such failures on the shop activities and road users.

Using Discrete-Event Simulation to Support Building Asset Management: An Exploratory Case Study

Among the Washington State Department of Transportation’s (WSDOT) capital assets, Transportation Equipment Fund (TEF) shops provide a crucial service by ensuring proper care and maintenance of most of the state vehicles and equipment. Therefore, any reduction of TEF shop facilities capabilities could jeopardize not only WSDOT vehicles and equipment maintenance but also WSDOT’s ability to fulfill its core mission. Given the importance of TEF shops, this exploratory case study analyzes the building system failures that have occurred or are likely to occur in these facilities, and utilizes discrete-event simulation to investigate how WSDOT operations can be affected by these events. In particular, by creating a model capable of simulating the service operations performed in the TEF shops, this study quantifies the consequences of failures on the shop activities and road users. The aim of this paper is to describe the development and validation of the discrete-event simulation model and its associated data gathering efforts. Whereas, further building systems failure analysis and impact assessment are within the scope of another publication.

Exploring the Relationship between Chronic Sleep Deprivation and Safety on Construction Sites

Evidence suggests that sleep deprivation can negatively affect behavior, wellbeing, and work performance. Although several researchers debated the relationships between sleep deprivation and work performance, research that clearly determines the relationship between construction workers’ sleep deprivation and safety performance has yet to be performed. To contribute to the analysis of such relationship, the researchers designed and administered a survey at three construction sites in Seattle (WA). The survey collected information about workers’ schedule, and sleeping habits and issues. The study concluded that most of the workers sleep between five to six hours before a working day and, therefore, could become the candidates to experience sleep deprivation related issues. Further, respondents were asked to rank the impact of sleep deprivation on the occurrence of ten types of near misses. Three types of near misses relating to the operation of forklifts, scissor lifts, trucks, or carts; the lack or improper use of personal protective equipment; and, the use of ladders were recognized as most likely to occur because of sleep deprivation. Thus, this study warrants that sleep deprivation might cause safety concerns for particular construction activities and that trade-specific investigation is necessary to clearly understand the relationship between sleep deprivation and safety.