A simulation-based decision-support system for integration of human cognition into construction operation planning

The mental workload associated with work activities is a key factor affecting the performance of human resources in labor-intensive construction operations, in turn impacting work behavior. While most accidents in construction are caused by unsafe behavior, modeling behavior in construction projects remains challenging and relatively unexplored. Here, human cognition is incorporated into the design of construction operations to analyze the mental task demands associated with various designs. A framework that integrates cognitive modeling with a simulation-based decision-support system capable of analyzing existing and non-existing operations in a simple and automated manner is proposed. The superiority of the proposed framework is that it eliminates the need for prior knowledge of the underlying cognitive theories. Functionality of the developed framework was evaluated following its application to a case study of welding operations, where the proposed method was shown to successfully evaluate the trade-off between mental workload and productivity for different operation scenarios

A Fuzzy Logic Approach to Posture-based Ergonomic Analysis for Field Observation and Assessment of Construction Manual Operations

In construction, workers are frequently exposed to ergonomic risks that can lead to musculoskeletal disorders. To prevent ergonomic injuries, proper assessment of ergonomic risk is a key to identifying risk factors and modifying work practice in a timely manner. In field observation, however, difficulties in visually estimating human postures (e.g., body joint angles) required for ergonomic analysis have led to inconsistent results due to the subjectiveness of observers. This study thus proposes a fuzzy logic approach to posture-based ergonomic evaluation tools. Rapid Upper Limb Assessment (RULA) is selected as a case study to describe the fuzzy logic modelling of RULA scoring systems and discuss the application to modular construction shops. The results of validation comparing correlations with biomechanical analysis—used as a ground truth—reveal that the proposed system produces more accurate results than traditional methods and hence helps minimize human errors in observation for reliable on-site ergonomic assessment.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Integration of predetermined motion time systems into simulation modeling of manual construction operations

Simulation modeling is a powerful tool widely used for designing construction processes and improving the efficiency of operations. However, there is often difficulty in estimating the duration of manual tasks for simulation purposes due to its dependence on the physical attributes of the worker performing the task. When designing a new process, there is usually a lack of sufficient data regarding the required duration for manual tasks, and in the case of evaluating and improving existing processes, there is no benchmark data for workers’ performance to enable comparison of the efficiency of the existing process. This study attempts to address this issue by exploring micro-motion-level simulation modeling in order to provide standard motion time required to perform a manual task for effective workplace design. The research method involves integrating a Predetermined Motion Time System (PMTS) into discrete event simulation, which provides the production planner with a standard task duration within which a worker must complete the task without delays or idling. As a case study, a manual task taking place in the production line of a construction steel fabrication company has been modeled using the developed automation tool in order to verify the feasibility of the proposed approach. The results show high correlation between the simulation model output and the actual time data from the jobsite and confirm the validity of the approach and its effectiveness in evaluating the productivity of the existing operations and providing detailed information for process improvement.Non UBCUnreviewedFacultyOthe

A case study of motion data-driven biomechanical assessment for identifying and evaluating ergonomic interventions in reinforced-concrete work

Physical ergonomic intervention (e.g., use of tools) is adopted to improve working postures in the reinforced-concrete trade. However, evaluating its effectiveness often focuses on a specific body part mostly concerned although posture modification in one part may physically affect another. This paper presents a case study to comprehensively examine the effectiveness of existing ergonomic interventions. In the experiment, a subject repeated typical motions 15 times, which served as the baseline of biomechanical simulation with the 50th percentile of the anthropometric size of the U.S. population. 3D-motion-capture and biomechanical simulation were then adopted to collect full-body posture data and compute the load exerted on body parts with population strength capability. The results indicated that the disc compressions and joint moments were reduced by 45.41% and 31.86% whereas the effectiveness varied among the body parts (e.g., elbow, shoulder, knee). These results suggest that ergonomic interventions can lessen physical demands by carefully selecting an appropriate intervention for specific tasks and body parts in practice

Effect of physiotherapy on quality of life after coronary artery bypass graft surgery: A randomized study

Background: This study aims to assess the impact that physiotherapy (PT) has on the quality of life (QoL) of patients who have undergone coronary artery bypass grafting (CABG) surgery. The objective of this study was to assess the effect of PT on physical and mental aspects of patients' QoL. Materials and Methods: The study population consisted of 50 patients who aged between 60 and 70 years and who had previously undergone CABG surgery. The patients were randomly allocated to two groups: a PT group (n = 25) and a control group (n = 25). The physical characteristics of the participants were recorded at the outset of the study. The patients who were allocated to the PT group completed 16 sessions of classic PT. QoL assessments of all participants were performed before and after the program in the form of a short form-36 health survey. An independent sample t-test and an ANCOVA were performed for the purpose of statistical analyses. Results: The QoL scores of the patients (mean age = 62.08 years) who underwent PT significantly improved after the intervention (P < 0.001). A significant difference between groups was observed (P < 0.001) in both the mental component summary and physical component summary variables. Conclusion: PT can help relieve pain, reduce depression, help patients more effectively perform the tasks of everyday living, and help ease the symptoms of other disabilities associated with cardiac surgery. In the current study, the implementation of a PT program improved the patient's mental health and increased their QoL

Socialization During the COVID-19 Pandemic: The Role of Social and Scientific Networks During Social Distancing

In the COVID-19 era, while we are encouraged to be physically far away from each other, social and scientific networking is needed more than ever. The dire consequences of social distancing can be diminished by social networking. Social media, a quintessential component of social networking, facilitates the dissemination of reliable information and fighting against misinformation by health authorities. Distance learning, telemedicine, and telehealth are among the most prominent applications of networking during this pandemic. Additionally, the COVID-19 pandemic highlights the importance of collaborative scientific efforts. In this chapter, we summarize the advantages of harnessing both social and scientific networking in minimizing the harms of this pandemic. We also discuss the extra collaborative measures we can take in our fight against COVID-19, particularly in the scientific field