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Mean-Variance Portfolio Analysis Data For Optimizing Community-Based Photovoltaic Investment

Shakouri, Mahmoud; Lee, Hyun Woo. (2016). Mean-Variance Portfolio Analysis Data For Optimizing Community-Based Photovoltaic Investment. Data In Brief, 6, 840 – 842.

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Abstract

The amount of electricity generated by Photovoltaic (PV) systems is affected by factors such as shading, building orientation and roof slope. To increase electricity generation and reduce volatility in generation of PV systems, a portfolio of PV systems can be made which takes advantages of the potential synergy among neighboring buildings. This paper contains data supporting the research article entitled: PACPIM: new decision-support model of optimized portfolio analysis for community-based photovoltaic investment [1]. We present a set of data relating to physical properties of 24 houses in Oregon, USA, along with simulated hourly electricity data for the installed PV systems. The developed Matlab code to construct optimized portfolios is also provided in Supplementary materials. The application of these files can be generalized to variety of communities interested in investing on PV systems. (C) 2016 The Authors. Published by Elsevier Inc.

Keywords

Community Solar; Photovoltaic System; Portfolio Theory; Energy Optimization; Electricity Volatility

Temporal Effect of Construction Workforce Physical Strain on Diminishing Marginal Productivity at the Task Level

Lee, Wonil; Migliaccio, Giovanni C. (2018). Temporal Effect of Construction Workforce Physical Strain on Diminishing Marginal Productivity at the Task Level. Journal Of Construction Engineering And Management, 144(9).

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Abstract

Physiological status and environmental stressors are known to influence workforce performance at the individual worker level. A previous study, which conducted a cross-sectional comparison in repetitive material-handling construction activities, suggested that a U-shaped relationship existed between physical strain and productivity at the group level. This research revisits those findings to further investigate the U-curve relationship between physical strain and productivity at the group level and validate the concept of diminishing marginal productivity. Heart rates were measured as an indicator of subjects' physical strain, whereas task productivity was estimated by work sampling. Eighty person-hour data were converted into panel data sets by dividing each subject's 4-h experimental data into 5-min intervals. These data sets were subsequently used to evaluate the effects of time on physical strain and productivity with 5-min lags. The study found a U-curve relationship between physical strain and task-level productivity at the group level while controlling for individual characteristics. The U-shape relationship was constant in the low-performance and high-performance groups, although the degrees of the polynomials differed. Productive workers will remain more productive than low-productive workers with increased physical strain.

Keywords

Construction Industry; Industrial Psychology; Labour Resources; Occupational Health; Polynomials; Productivity; Physiological Status; Environmental Stressors; U-shaped Relationship; Productive Workers; Polynomials Degree; Diminishing Marginal Productivity; Construction Workforce Physical Strain; Labor Productivity; Scientific Management; Shift Work; Performance; Model; Taylorism; Burnout; Design; Impact; Safety; Construction Productivity; Labor And Personal Issue; Work Physiology; Physical Strain

Application of Prevention Through Design (PTD) to Improve the Safety of Solar Installations on Small Buildings

Ho, Chung; Lee, Hyun Woo; Gambatese, John A. (2020). Application of Prevention Through Design (PTD) to Improve the Safety of Solar Installations on Small Buildings. Safety Science, 125.

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Abstract

As a viable, clean and renewable energy resource, solar energy has gained a significant interest in the US residential sector. Most solar systems are installed on rooftops to take advantage of available space and reduce land use. However, this installation environment also exposes workers to unique safety hazards related to existing roof conditions such as slippery roofing materials, irregular roof layouts, and steep roof slopes. Although Prevention through Design (ND) has been widely considered as an effective way to address safety issues during the design phase, little to no studies have applied ND to improve safety in solar energy installations. To fill this knowledge gap, this research aimed to investigate how, during the design phase, to address the safety concerns of solar workers when installing solar energy systems on residential buildings. Through a series of interviews, four case studies, and a seminar, seven solar ND attributes were identified: roofing materials, roof slopes, roof accessories, panel layouts, fall protection systems, lifting methods and electrical systems. Based on the attributes, a ND protocol was developed that can serve as guidance for implementing ND in solar installations. This paper presents the research activities and findings, and feedback gained from solar contractors through a seminar on the study. The study is expected to contribute to reducing safety hazards by implementing ND, help improve safety performance in solar installations on small residential buildings and support the promotion of safety in sustainable construction.

Keywords

Roofing Materials; Renewable Energy Sources; Sustainable Construction; Solar Energy; Clean Energy; Construction Safety; Prevention Through Design; Small Buildings; Solar Installations; Buildings (structures); Construction Industry; Hazards; Occupational Safety; Roofs; Safety; Solar Power; Sustainable Development; Steep Roof Slopes; Design Phase; Solar Energy Installations; Solar Workers; Installing Solar Energy Systems; Residential Buildings; Seven Solar Ptd Attributes; Roof Accessories; Ptd Protocol; Solar Contractors; Safety Performance; Viable Energy Resource; Clean Energy Resource; Renewable Energy Resource; Us Residential Sector; Solar Systems; Installation Environment; Unique Safety Hazards; Roof Conditions; Slippery Roofing Materials; Irregular Roof Layouts; Issues; Accident Prevention; Protocol; Energy Sources; Residential Areas; Land Use; Prevention; Design; Falls; Occupational Hazards; Contractors; Residential Energy; Protection Systems; Renewable Energy; Buildings; Roofing; Layouts

Accelerated Construction of Urban Intersections with Portland Cement Concrete Pavement (PCCP)

Nemati, Kamran M.; Uhlmeyer, Jeff S. (2021). Accelerated Construction of Urban Intersections with Portland Cement Concrete Pavement (PCCP). Case Studies In Construction Materials, 14.

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Abstract

The frequent maintenance required on asphalt concrete (AC) pavement sections has made reconstruction with portland cement concrete pavement (PCCP) a feasible alternative. However, many constructability issues need to be addressed in order to realize the full potential of this alternative. Accelerated paving encompasses three classes of activities: methods to accelerate the rate of strength gain, methods to minimize the construction time, and traffic control strategies to minimize user delay. In this paper a case study will be presented in which an AC intersection was reconstructed with portland cement concrete pavement. The entire reconstruction of the intersection, including demolition of the AC pavement and its replacement with PCCP, took place over a period of three days, starting on Thursday evening and opening the intersection to the traffic on Sunday afternoon. This paper documents this effort in order to provide practitioners additional options for rapid reconstruction of urban intersections and includes documentation of the construction process, traffic management strategies, and an analysis of the costs. The results of this investigation can be used to educate pavement construction professionals and the academic community on the use of PCCP for accelerated reconstruction of major urban intersections with minimal user and traffic disruption, using innovative construction techniques and traffic management optimization principles. This investigation produced valuable information to demonstrate that concrete pavements can be constructed efficiently and quickly. (C) 2021 The Authors. Published by Elsevier Ltd.

Keywords

Concrete; Accelerated Construction; Pavement; Portland Cement Concrete Pavement; Maturity Method

Organizational Divisions in BIM-Enabled Commercial Construction

Dossick, Carrie S.; Neff, Gina. (2010). Organizational Divisions in BIM-Enabled Commercial Construction. Journal Of Construction Engineering And Management-asce, 136(4), 459 – 467.

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Abstract

Proponents claim that the adoption of building information modeling (BIM) will lead to greater efficiencies through increased collaboration. In this paper, we present research that examines the use of BIM technologies for mechanical, electrical, plumbing, and fire life safety systems (often referred to as MEP) coordination and how the introduction of BIM influences collaboration and communication. Using data from over 12 months of ethnographic observations of the MEP coordination process for two commercial construction projects and interviews with 65 industry leaders across the United States, we find that BIM-enabled projects are often tightly coupled technologically, but divided organizationally. This means that while BIM makes visible the connections among project members, it is not fostering closer collaboration across different companies. We outline the competing obligations to scope, project, and company as one cause for this division. Obligations to an individual scope of work or to a particular company can conflict with project goals. Individual leadership, especially that of the MEP coordinator in the teams we studied, often substitutes for stronger project cohesion and organization. Organizational forces and structures must be accounted for in order for BIM to be implemented successfully.

Keywords

Technology; Implementation; Viewpoint; Integrated Systems; Construction Industry; Leadership; Information Systems; Information Technology; Communication; Constructability; Mechanical Systems; Electrical Systems

Quantifying the Impact of Facilitation on Transactive Memory System Formation in Global Virtual Project Networks

Comu, Semra; Iorio, Josh; Taylor, John E.; Dossick, Carrie Sturts. (2013). Quantifying the Impact of Facilitation on Transactive Memory System Formation in Global Virtual Project Networks. Journal Of Construction Engineering & Management, 139(3), 294 – 303.

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Abstract

Building strong ties between geographically dispersed project participants is crucial to project success. In global project networks, many firms have adopted virtual collaboration tools to address the challenges imposed by temporal and geographical distance. Some researchers have examined the role of facilitators and found that process facilitation can improve collaboration. Research has also shown that facilitators can be drawn into content interactions, which may negatively impact collaboration effectiveness in virtual workspaces. Research to date has not quantified this negative impact. In this study, the formation and maintenance of transactive memory systems (TMS) in two facilitated and two nonfacilitated global virtual project networks were investigated, each executing a 2-month project. Using TMS formation and cohesive subgroup formation as a proxy for performance, quantitative evidence was found that demonstrates a negative impact on collaboration effectiveness when facilitators engage in content facilitation in virtual project networks. This paper shows that this negative impact restricts the establishment of TMSs. These findings have important implications for understanding and designing appropriate facilitator interactions in global virtual project networks. DOI: 10.1061/(ASCE)CO.1943-7862.0000610. (C) 2013 American Society of Civil Engineers.

Keywords

Globalisation; Groupware; International Collaboration; Production Engineering Computing; Project Management; Process Facilitation; Transactive Memory System Formation; Global Virtual Project Network; Virtual Collaboration Tool; Temporal Distance; Geographical Distance; Content Interaction; Virtual Workspace; Tms Cohesive Subgroup Formation; Content Facilitation; Knowledge Transfer; Group Cohesiveness; Group Cohesion; Performance; Teams; Models; Globalization; Networks; Project Networks; Social Network Analysis; Transactive Memory Systems; Virtual Teams

Physiological Condition Monitoring of Construction Workers.

Gatti, Umberto C.; Schneider, Suzanne; Migliaccio, Giovanni C. (2014). Physiological Condition Monitoring of Construction Workers. Automation In Construction, 44, 227 – 233.

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Abstract

Monitoring of workers' physiological conditions can potentially enhance construction workforce productivity, safety, and well-being. Recently, Physiological Status Monitors (PSMs) were validated as an accurate technology to assess physiological conditions during typical sport science and medicine testing procedures (e.g., treadmill and cycle ergometer protocols). However, sport science and medicine testing procedures cannot simulate routine construction worker movements in a comprehensive manner. Thus, this paper investigated the validity of two PSMs by comparing their measurements with gold standard laboratory instruments' measurements at rest and during dynamic activities resembling construction workforce's routine activities. Two physiological parameters such as heart rate and breathing rate were considered. Ten apparently healthy subjects participated in the study. One of the PSMs proved to be a viable technology in assessing construction workers' heart rate (correlation coefficient >= 0.74; percentage of differences within +/- 11 bpm >= 84.8%). (C) 2014 Elsevier B.V. All rights reserved,

Keywords

Construction Workers; Labor Supply; Labor Productivity; Well-being; Health Status Indicators; Heart Rate Monitoring; Physiology; Construction Management; Construction Worker; Ergonomics; Occupational Health And Safety; Physiological Status Monitoring Technology; Productivity; Work Physiological Demand; Work Physiology; Construction Industry; Monitoring; Occupational Safety; Medicine Testing; Sport Science; Psm; Physiological Status Monitors; Safety; Construction Workforce Productivity; Workers Monitoring; Physiological Condition Monitoring; Heart-rate Monitors; R-r Intervals; Statistical-methods; Respiratory Rate; Physical Load; Polar S810; Strain; Validity; Reliability; Validation

BIM Curriculum Design in Architecture, Engineering, and Construction Education: A Systematic Review

Abdirad, Hamid; Dossick, Carrie S. (2016). BIM Curriculum Design in Architecture, Engineering, and Construction Education: A Systematic Review. Journal Of Information Technology In Construction, 21, 250 – 271.

Abstract

In the past several years, Building Information Modeling (BIM) adoption has grown significantly in the architecture, engineering, and construction (AEC) industry. In response to this trend, the industry and academia realized that BIM education in university curricula is an important requirement for satisfying educational demands of the industry, and a notable body of research has reported strategies AEC programs implemented to incorporate BIM in their curricula. However, no study has comprehensively reviewed and synthesized the research on sfrategies adopted by educators. To bridge this gap in the literature, this paper presents a systematic review of research on BIM curriculum design in AEC education. The authors report on the trends of research on BIM curriculum design (e.g. methods, timelines, and contexts) as well as a synthesis of implemented pedagogical strategies with detailed discussions on their implications and effectiveness across different studies and contexts. These strategies address a variety of important pedagogical issues such as enrolment of students, optional or required BIM use, important competencies and skills, tutoring methods, industry engagement, designing assignments, and assessment methods and criteria. This synthesis shows that designing pedagogical sfrategies for BIM education is complex and challenging, and AEC programs need to make trade-offs between advantages and disadvantages associated with these strategies. The results also highlight the need for more diverse research designs and settings to bridge the gaps identified in BIM curriculum research to date. Finally, the authors present a literature-based framework of BIM curriculum design sfrategies as well as a set of recommendations that can be used BIM educators and researchers as a guide for designing or assessing their BIM curricula in future research.

Keywords

Bridges; Curricula; Economic And Social Effects; Education; Information Theory; Personnel Training; Reviews; Students; Architecture; Engineering; And Constructions; Building Information Model; Bim; Curriculum Designs; Pedagogical Issues; Pedagogical Strategies; Research Designs; Systematic Review; University Curricula; Industry; Management; Building Information Modeling; Training; Curriculum; Review

The Impact of Avatars, Social Norms and Copresence on the Collaboration Effectiveness of AEC Virtual Teams

Anderson, Anne; Dossick, Carrie Sturts; Iorio, Josh; Taylor, John E. (2017). The Impact of Avatars, Social Norms and Copresence on the Collaboration Effectiveness of AEC Virtual Teams. Journal Of Information Technology In Construction, 22, 287 – 304.

Abstract

A growing number of architecture, engineering, and construction (AEC) firms are outsourcing complex design and construction work to international vendors. Due to the significant geographic distances that can separate project team members in global design networks, much of this work is executed in virtual teams, defined as teams composed of geographically separated members who collaborate to accomplish organizational tasks mediated by technology. The challenges of working in geographically distributed networks have prompted the development of alternative, virtual workspaces. Questions remain on how these virtual workspaces support or hinder collaborative work. People are social beings that rely on body language and other non-verbal cues to communicate. What happens to team formation and collaborative effectiveness when non-verbal cues are mediated through avatar actions? In this paper, qualitative ethnographic data collected over four years from studies conducted in a 3D virtual world are used to examine collaboration effectiveness of global virtual engineering project teams. We found that avatar movement and position was effective at communicating nonverbal information, even when done so unintentionally. Avatar actions that map to established social norms in the physical world results in more efficient communication. Collaboration was also enhanced when gesture bubbles were used for backchannel communication and when text chat was used to avoid interrupting voice communication. We found collaboration was hindered when the learning curve was too steep for participants to adapt to tool use or avatar actions in the environment. These findings have important implications for the future of collaboration in virtual environments, particularly in the AEC industry where 3D models can be imported into the virtual environment and explored synchronously by a project team.

Keywords

Architectural Design; Human Resource Management; International Trade; Bim Coordination; Collaboration Technology; Distributed Teams; Social Norm; Virtual Worlds; Communication; Design; Technology; Dimensions; Teamwork; Behavior; Collaboration Technologies; Social Norms

Understanding The Social Contagion Effect Of Safety Violations Within A Construction Crew: A Hybrid Approach Using System Dynamics And Agent-based Modeling

Liang, Huakang; Lin, Ken-yu; Zhang, Shoujian. (2018). Understanding The Social Contagion Effect Of Safety Violations Within A Construction Crew: A Hybrid Approach Using System Dynamics And Agent-based Modeling. International Journal Of Environmental Research And Public Health, 15(12).

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Abstract

Previous research has recognized the importance of eliminating safety violations in the context of a social group. However, the social contagion effect of safety violations within a construction crew has not been sufficiently understood. To address this deficiency, this research aims to develop a hybrid simulation approach to look into the cognitive, social, and organizational aspects that can determine the social contagion effect of safety violations within a construction crew. The hybrid approach integrates System Dynamics (SD) and Agent-based Modeling (ABM) to better represent the real world. Our findings show that different interventions should be employed for different work environments. Specifically, social interactions play a critical role at the modest hazard levels because workers in this situation may encounter more ambiguity or uncertainty. Interventions related to decreasing the contagion probability and the safety-productivity tradeoff should be given priority. For the low hazard situation, highly intensive management strategies are required before the occurrence of injuries or accidents. In contrast, for the high hazard situation, highly intensive proactive safety strategies should be supplemented by other interventions (e.g., a high safety goal) to further control safety violations. Therefore, this research provides a practical framework to examine how specific accident prevention measures, which interact with workers or environmental characteristics (i.e., the hazard level), can influence the social contagion effect of safety violations.

Keywords

Risk-taking; Coworker Support; Employee Safety; Job Demands; Work Groups; Behavior; Climate; Impact; Performance; Simulation; Social Contagion Effect; Routine Safety Violations; Situational Safety Violations; System Dynamics; Agent-based Simulation; Research; Violations; Modelling; Accident Prevention; Social Factors; Safety; Organizational Aspects; Occupational Safety; Construction; Influence; Construction Accidents & Safety; Workers; Safety Management; Information Processing; Construction Industry; Hybrid Systems; Social Interactions; Cognitive Ability; Human Error; Accident Investigations