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Department: College of Built Environments

Developing a Decision-Making Framework to Select Safety Technologies for Highway Construction

Nnaji, Chukwuma; Lee, Hyun Woo; Karakhan, Ali; Gambatese, John. (2018). Developing a Decision-Making Framework to Select Safety Technologies for Highway Construction. Journal Of Construction Engineering And Management, 144(4).

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Abstract

Highway construction has consistently reported relatively high fatality rates largely because of the considerable exposure of workers to live traffic. To address this anomaly, traffic control planners are tasked with making decisions geared toward reducing hazardous situations caused by transiting vehicles and construction equipment. The growing application of technologies to enhance worker safety should be considered during the traffic control planning process. In certain cases, decisions such as choosing among technology options are made using experiential individual knowledge without the application of scientific and systematic decision-making methods. Use of experience-based decision making in this context is largely the result of sparse literature on scientific methods of selecting between alternatives in highway construction work zones. By applying the Choosing by Advantages (CBA) decision-making method, a process that achieves sound and effective decisions, the current study aims to fill the gap in practice by proposing a decision-making framework that could enhance the value-cost selection process of safety technologies in highway construction work zones. A situation that applied work zone intrusion alert technologies (WZIATs) was selected as a case study. Using a focus group session and case projects as an evaluation study process, the proposed framework based on the CBA decision-making process was applied to evaluate three WZIATs. Findings from the current study will benefit safety professionals and practitioners by providing a step-by-step approach to make sound decisions that can enhance the level of safety in highway construction work zones.

Keywords

Construction Equipment; Decision Making; Occupational Safety; Project Management; Road Building; Effective Decisions; Decision-making Framework; Value-cost Selection Process; Highway Construction Work Zones; Work Zone Intrusion Alert Technologies; Cba Decision-making Process; Sound Decisions; Traffic Control Planners; Worker Safety; Traffic Control Planning Process; Technology Options; Scientific Decision-making Methods; Systematic Decision-making Methods; Experience-based Decision Making; Advantages Decision-making Method; Safety Technologies; Knowledge; Signs

High Delinquency Rates in Brazil’s Minha Casa Minha Vida Housing Program: Possible Causes and Necessary Reforms

Acolin, Arthur; Hoek-Smit, Marja C.; Eloy, Claudia Magalhaes. (2019). High Delinquency Rates in Brazil’s Minha Casa Minha Vida Housing Program: Possible Causes and Necessary Reforms. Habitat International, 83, 99 – 110.

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Abstract

Brazil's main housing program, Minha Casa Minha Vida (MCMV), has contracted the construction of over 3 million housing units since 2009, providing access to homeownership for low and middle-income households through a combination of credit, subsidies and guarantees. In this paper, we analyze disaggregated delinquency information at the project level for the section of the program that serves households in the lowest income range (Faixa 1). Our analysis of program performance in six metropolitan regions shows an overall level of delinquency of 28% as of the end of 2015. We identify four hypotheses to explain this elevated level of delinquency: the peripheral location of the units, insufficient income to cover ongoing costs, moral hazard in the management of the program, and organized crime in some projects. Our analysis shows that in 4 of the 6 regions, low-income projects in peripheral locations exhibit substantially higher non-payment levels and that lower income households have higher levels of delinquency. Based on our analysis, we recommend modifications to program design, including the inclusion of location criteria in subsidy scaling. The findings provide evidence of the limits of MCMV Faixa l's approach to solving Brazilian low-income housing needs and contribute to an emerging body of literature pointing to the importance of location in housing programs.

Keywords

Income; Urban Growth; Housing; Home Ownership; Moral Hazard; Affordable Housing; Delinquency Rate; Housing Program; Integrated Urban Development; Programa Minha Casa Minha Vida; Social Housing; Mexico; Scale

Perceptions and Expected Immediate Reactions to Severe Storm Displays

Jon, Ihnji; Huang, Shih-Kai; Lindell, Michael K. (2019). Perceptions and Expected Immediate Reactions to Severe Storm Displays. Risk Analysis, 39(1), 274 – 290.

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Abstract

The National Weather Service has adopted warning polygons that more specifically indicate the risk area than its previous county-wide warnings. However, these polygons are not defined in terms of numerical strike probabilities (p(s)). To better understand people's interpretations of warning polygons, 167 participants were shown 23 hypothetical scenarios in one of three information conditions-polygon-only (Condition A), polygon + tornadic storm cell (Condition B), and polygon + tornadic storm cell + flanking nontornadic storm cells (Condition C). Participants judged each polygon's p(s) and reported the likelihood of taking nine different response actions. The polygon-only condition replicated the results of previous studies; p(s) was highest at the polygon's centroid and declined in all directions from there. The two conditions displaying storm cells differed from the polygon-only condition only in having p(s) just as high at the polygon's edge nearest the storm cell as at its centroid. Overall, p(s) values were positively correlated with expectations of continuing normal activities, seeking information from social sources, seeking shelter, and evacuating by car. These results indicate that participants make more appropriate p(s) judgments when polygons are presented in their natural context of radar displays than when they are presented in isolation. However, the fact that p(s) judgments had moderately positive correlations with both sheltering (a generally appropriate response) and evacuation (a generally inappropriate response) suggests that experiment participants experience the same ambivalence about these two protective actions as people threatened by actual tornadoes.

Keywords

Decision-making; Tornado; Risk; Communication; Numeracy; Residents; Shelter; Events; Protective Actions; Risk Perceptions; Tornado Warning Polygons; Judgments; Tornadoes; Meteorological Services; Storms; Lymphocytes B; Polygons; Emergency Warning Programs; Evacuation; Displays; Inappropriateness; Weather; Warnings; Conditions; Ambivalence

The Complexity of Urban Eco-Evolutionary Dynamics

Alberti, Marina; Palkovacs, Eric P.; Des Roches, Simone; De Meester, Luc; Brans, Kristien, I; Govaert, Lynn; Grimm, Nancy B.; Harris, Nyeema C.; Hendry, Andrew P.; Schell, Christopher J.; Szulkin, Marta; Munshi-south, Jason; Urban, Mark C.; Verrelli, Brian C. (2020). The Complexity of Urban Eco-Evolutionary Dynamics. Bioscience, 70(9), 772 – 793.

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Abstract

Urbanization is changing Earth's ecosystems by altering the interactions and feedbacks between the fundamental ecological and evolutionary processes that maintain life. Humans in cities alter the eco-evolutionary play by simultaneously changing both the actors and the stage on which the eco-evolutionary play takes place. Urbanization modifies land surfaces, microclimates, habitat connectivity, ecological networks, food webs, species diversity, and species composition. These environmental changes can lead to changes in phenotypic, genetic, and cultural makeup of wild populations that have important consequences for ecosystem function and the essential services that nature provides to human society, such as nutrient cycling, pollination, seed dispersal, food production, and water and air purification. Understanding and monitoring urbanization-induced evolutionary changes is important to inform strategies to achieve sustainability. In the present article, we propose that understanding these dynamics requires rigorous characterization of urbanizing regions as rapidly evolving, tightly coupled human-natural systems. We explore how the emergent properties of urbanization affect eco-evolutionary dynamics across space and time. We identify five key urban drivers of change-habitat modification, connectivity, heterogeneity, novel disturbances, and biotic interactions-and highlight the direct consequences of urbanization-driven eco-evolutionary change for nature's contributions to people. Then, we explore five emerging complexities-landscape complexity, urban discontinuities, socio-ecological heterogeneity, cross-scale interactions, legacies and time lags-that need to be tackled in future research. We propose that the evolving metacommunity concept provides a powerful framework to study urban eco-evolutionary dynamics.

Keywords

Habitat Modification; Seed Dispersal; Water Purification; Species Diversity; Human Behavior; Ecosystem Services; Nutrient Cycles; Cross-scale Interactions; Ecological Consequences; Contemporary Evolution; Gradient Analysis; Trophic Dynamics; Land-cover; Community; Biodiversity; Adaptation; Urban Ecology; Eco-evolutionary Dynamics; Coupled Human-natural Systems; Metacommunities; Ecology; Urbanization; Evolution; Water Treatment; Environmental Monitoring; Species Composition; Environmental Changes; Play; Food Production; Air Purification; Sustainability; Dynamic Tests; Air Monitoring; Urban Areas; Food Webs; Heterogeneity; Food Chains; Pollination; Dynamics; Complexity; Dispersal; Microclimate

Comparative Environmental Analysis of Seismic Damage in Buildings

Huang, M.; Simonen, K. (2020). Comparative Environmental Analysis of Seismic Damage in Buildings. Journal Of Structural Engineering, 146(2).

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Abstract

In studying the environmental impacts of buildings, earthquake hazards are rarely considered, but their environmental impacts can be significant. This case study paper demonstrates how the US Federal Emergency Management Agency's Performance Assessment Calculation Tool (PACT) can be used to analyze the environmental impacts of buildings using probabilistic seismic hazard assessment. PACT was used to evaluate 10 case study buildings that varied by five types of lateral systems and two risk categories. For each building, PACT generated 1,000 realizations at five earthquake intensities. The resulting environmental impacts were analyzed according to their distribution, median, and average values, and the differences among building component types, risk categories, and lateral force-resisting systems were explored. In this study, building components that were categorized under Exterior Enclosures, Interior Finishes, and Heating, Ventilation, and Air-Conditioning (HVAC) produced notably higher environmental impacts in response to seismic damage, and their vulnerability to displacement- or acceleration-induced damage could be attributed to the characteristics of the lateral systems. Although these observations are notable, they should not be taken as universally applicable to all buildings. Instead, these findings exemplify how the environmental impact results from PACT can be analyzed and interpreted to address both the seismic and environmental aspects of building design. (C) 2019 American Society of Civil Engineers.

Keywords

Impact

Improving Construction Work Zone Safety Using Technology: A Systematic Review of Applicable Technologies

Nnaji, Chukwuma; Gambatese, John; Lee, Hyun Woo; Zhang, Fan. (2020). Improving Construction Work Zone Safety Using Technology: A Systematic Review of Applicable Technologies. Journal Of Traffic And Transportation Engineering (english Edition), 7(1), 61 – 75.

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Abstract

Once considered conventional, the construction industry is gradually increasing its reliance on innovations such as the application of technologies in safety management. Given the growing literature on technology applications in safety management and the varying opinions on the utility of applied technologies, a systematic review that streamlines findings from past studies is indispensable to construction stakeholders. Although a number of review studies are available in the building construction sector, the level of fragmentation and uniqueness within the construction industry necessitates a review study specifically targeting the heavy civil sector. In response, the present study applies a three-step approach to identify and review articles pertinent to the safety of highway construction work zones. The factors considered include the number of publications per year, publication locations, and technology types. In addition, the present study proposes to broadly group work zone safety technologies (WZSTs) into three categories based on their primary purpose: speed reduction systems, intrusion prevention and warning systems, and human-machine-interaction detection systems. Key findings include WZST research trends, application of smart work zone systems, and the potential relationship between WZSTs and fatalities. The paper ends with the identification of six additional research areas aimed at deepening the understanding of technology's role in highway safety management. The trend analysis and an in-depth discussion of each technology category alongside the identified research gaps will provide a substantial informative body of knowledge that both benefits current practitioners and directs researchers towards potential future studies. (C) 2019 Periodical Offices of Changan University. Publishing services by Elsevier B.V. on behalf of Owner.

Keywords

Automated Speed Enforcement; Drivers Visual Performance; Rumble Strips; Message Signs; Radar; Management; Adoption; Crashes; Transportation; Work Zone; Worker Safety; Technology Application; Safety Technology; Systematic Review

Syncing with the Sky: Daylight-Driven Circadian Lighting Design

Altenberg Vaz, Nathan; Inanici, Mehlika. (2021). Syncing with the Sky: Daylight-Driven Circadian Lighting Design. Leukos, 17(3), 291 – 309.

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Abstract

The use of daylight in the built environment is often preferred to artificial light sources as its successful application can provide visual comfort and satisfaction along with the potential for significant energy savings. Exposure to daylight is also the primary source for stimulus that establishes a healthy day/night cycle in all living organisms. This is known as circadian rhythm. Newly discovered photoreceptors (intrinsically photosensitive retinal ganglion cells - ipRGC) within the mammalian eye, including humans, are specifically linked to the portion of the brain responsible for maintaining a healthy circadian rhythm. This discovery has led to a new subject area in the field of lighting design focused on controlling the spectrum of light that these photoreceptors are sensitive to. Currently, work in the field of circadian lighting design is concentrated on the use of artificial light sources for circadian stimulus. This is largely due to the advent of the widespread use of LED technology, which has proven that it can be a significant source of light that can delay or advance the circadian clock. The use of daylight to provide circadian stimulus has been a given in this field of design, however, there has not been very much research into how the built environment affects our ability to effectively receive this stimulus from daylight. In this research, the groundwork is established to start to create a set of guidelines to help architects and designers maximize the potential for daylight to provide circadian stimulus at the earliest stages of a project. This is accomplished through a series of lighting simulations that explore and test various architectural parameters that affect daylight-driven circadian lighting, with simultaneous consideration given to photopic lighting availability and visual comfort. The architectural parameters tested in this study included window head height, building orientation, shading devices, visual obstructions to the sky, and room depth. The results show that informed design decisions could maximize circadian potential in a given space, while achieving visually satisfactory luminous environments.

Keywords

Action Spectrum; Melanopsin; Environments; Sensitivity; Framework; Stimulus; Rod; Circadian Lighting; Daylight; Lighting Simulation; Alfa

Autonomous People: Identity, Agency, and Automated Driving

Dunn, Peter T. (2021). Autonomous People: Identity, Agency, and Automated Driving. Journal Of Urban Technology, 28(3-4), 25 – 44.

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Abstract

The prevailing discourse on autonomous vehicles (AVs) has not yet developed a sophisticated conceptualization of autonomy and has given insufficient attention to the autonomy of people. In response, this article shifts our attention away from the AV's autonomy and towards that of its user. Autonomy is conceived here as the socially and materially situated capacity of an individual to identify and act on one's own values and desires, a capacity that is desirable for collective political life. This definition is drawn selectively from a survey of thought illustrating the richness of this concept. I then examine how studies of transportation have already made use of certain themes of autonomy in understanding mobility practices beyond dominant utilitarian models. This sets up an examination of AVs, where the existing literature tends to use a narrow conceptualization of autonomy. I then briefly examine two examples of unsettled questions in AV development, discretionary user controls and shared ride systems, in light of autonomy. The goal of this article is both to show how autonomy can be productive in understanding mobility practices, and to argue for personal autonomy as a normative value worth pursuing in the technical, political, and social development of automated mobility systems.

Keywords

Car Use; Vehicles; Travel; Accidents; Policy; Autonomy; Agency; Autonomous Vehicles; Mobility

Biophilic Photobiological Adaptive Envelopes for Sub-Arctic Buildings: Exploring Impacts of Window Sizes and Shading Panels’ Color, Reflectance, and Configuration

Parsaee, Mojtaba; Demers, Claude M. H.; Potvin, Andre; Lalonde, Jean-Francois; Inanici, Mehlika; Hebert, Marc. (2021). Biophilic Photobiological Adaptive Envelopes for Sub-Arctic Buildings: Exploring Impacts of Window Sizes and Shading Panels’ Color, Reflectance, and Configuration. Solar Energy, 220, 802 – 827.

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Abstract

Northern building envelopes must provide efficient indoor-outdoor connections based on photobiologicalpsychological needs of occupants for positive relationships with the sub-Arctic nature, particularly daylighting and day/night cycles. Envelope configurations of Northern Canada's buildings have not yet considered such requirements. Potentials of adaptive systems are also still limited. This research develops a fundamental model of adaptive multi-skin envelopes for sub-Arctic buildings based on main biophilic and photobiological indicators which characterize efficient indoor-outdoor connections. Biophilic indicators characterize the state of connections among occupants and outdoors which could stimulate biological-psychological responses. Photobiological indicators determine human-centric lighting adaptation scenarios for hourly lighting qualities and sufficient darkness in relation to local day/night cycles and daylighting. Biophilic performance of the proposed envelope was evaluated through 18 numerical models in terms of impacts of window and shading sizes on occupants' field of views. Photobiological lighting performance was evaluated by experimental methods using 23 physical models at 1:10 scale. Surface characteristics of dynamic shading panels, including color, reflectance, orientation, and inclination, were studied for potential photobiological impacts in terms of melanopic/photopic ratios and color temperatures. Results show that the proposed envelope could (i) offer acceptable direct visual connections with the outdoor nature through efficient window sizes for biophilia, and (ii) modify daylighting qualities to address hourly/seasonal photobiological needs of sub-Arctic occupants. Challenges of the proposed envelope to implement under sub-Arctic climatic conditions are underlined especially in terms of energy issues. The research outcomes help architects and decision-makers to improve occupants' wellbeing and healthy buildings in subArctic climates.

Keywords

Window Shades; Building Envelopes; Reflectance; Color Temperature; Daylighting; Building-integrated Photovoltaic Systems; Daylight; Outdoor Living Spaces; Canada; Adaptive Envelope; Arctic Climate; Biophilic Design; Healthy Building; Photobiological Lighting; Light; Exposure; Stress; Design; Architecture; Sensitivity; Illuminance; Environment; Melatonin; Recovery; Surface Properties; Performance Evaluation; Indicators; Polar Environments; Lighting; Shading; Darkness; Decision Making; Envelopes; Configurations; Buildings; Color; Adaptive Systems; Climatic Conditions; Numerical Models; Mathematical Models; Panels; Night; Climate; Orientation; Arctic Region