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
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
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
Wang, Lan; Zhang, Surong; Yang, Zilin; Zhao, Ziyu; Moudon, Anne Vernez; Feng, Huasen; Liang, Junhao; Sun, Wenyao; Cao, Buyang. (2021). What County-level Factors Influence Covid-19 Incidence in the United States? Findings from the First Wave of the Pandemic. Cities, 118.
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Abstract
Effective control of the COVID-19 pandemic via appropriate management of the built environment is an urgent issue. This study develops a research framework to explore the relationship between COVID-19 incidence and influential factors related to protection of vulnerable populations, intervention in transmission pathways, and provision of healthcare resources. Relevant data for regression analysis and structural equation modeling is collected during the first wave of the pandemic in the United States, from counties with over 100 confirmed cases. In addition to confirming certain factors found in the existing literature, we uncover six new factors significantly associated with COVID-19 incidence. Furthermore, incidence during the lockdown is found to significantly affect incidence after the reopening, highlighting that timely quarantining and treating of patients is essential to avoid the snowballing transmission over time. These findings suggest ways to mitigate the negative effects of subsequent waves of the pandemic, such as special attention of infection prevention in neighborhoods with unsanitary and overcrowded housing, minimization of social activities organized by neighborhood associations, and contactless home delivery service of healthy food. Also worth noting is the need to provide support to people less capable of complying with the stay-at-home order because of their occupations or socio-economic disadvantage.
Keywords
Pandemics; Covid-19; Covid-19 Pandemic; Infection Prevention; Stay-at-home Orders; Structural Equation Modeling; United States; Communicable Disease Prevention; Influential Factors; Lockdown; Structural Equation Modeling (sem); Prevalence; Disease; Healthy Food; Social Activities; Counties; Neighborhoods; Housing; Built Environment; Prevention; Minimization; Socioeconomic Factors; Intervention; Health Care; Vulnerability; Occupations; Coronaviruses; Food Service; Disease Transmission; United States--us
Aziz, Ahmed M. Abdel. (2021). The Practice of Roadway Safety Management in Public-Private Partnerships. Journal Of Construction Engineering And Management, 147(12).
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Abstract
As a matter of course, the private party in public-private partnerships (PPPs) assumes the responsibility for roadway safety management (RSM). However, because most PPPs are performance-based, public highway agencies must articulate the specifications and methods they develop to enforce RSM practices. Despite the increased interest in PPPs in recent decades, little has been published on developing and propagating the RSM practices used with this delivery system. To fill this research gap and explore RSM practices in PPPs, this work took a synthesis research approach, using content analysis to critically review and analyze 16 PPP agreements in seven states and provinces leading in PPP contracting in North America. The study discovered several methods and organized them under five mechanisms: Mechanism 1, integrating roadway safety into project performance specifications and initiating new tools such as safety compliance orders; Mechanism 2, imposing nonconformance monetary deductions based on point and classification systems; Mechanism 3, regulating safety payments on the basis of crash statistics; Mechanism 4, promoting safety initiative programs; and Mechanism 5, enforcing administrative countermeasures such as work suspension and default/termination triggers for persistent developer noncompliance. Mechanisms 1 and 5 were the default mechanisms in all toll- and availability-based projects, whereas Mechanism 2 was common in availability-only projects. The research reviewed the RSM packages in the PPP agreements, elucidating the particulars of the RSM mechanisms, highlighting RSM design considerations, presenting implementation guidelines, and articulating research needs. The research results were validated against PPP highways in five other states and provinces. This synthesis research provides highway agencies with an extensive practice review to support RSM package design for future PPP projects.
Keywords
Qualitative Research; Incentives; Public-private Partnerships (ppps); Performance Specifications; Roadway Safety; Payment Mechanisms; Availability Payment; Highways
Firth, Caislin L.; Baquero, Barbara; Berney, Rachel; Hoerster, Katherine D.; Mooney, Stephen J.; Winters, Meghan. (2021). Not Quite a Block Party: Covid-19 Street Reallocation Programs in Seattle, WA and Vancouver, BC. Ssm-population Health, 14.
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Abstract
The COVID-19 pandemic has exposed mobility inequities within cities. In response, cities are rapidly implementing street reallocation initiatives. These interventions provide space for walking and cycling, however, other mobility needs (e.g., essential workers, deliveries) may be impeded by these reallocation decisions. Informed by mobility justice frameworks, we examined socio-spatial differences in access to street reallocations in Seattle, Washington and Vancouver, British Columbia. In both cities, more interventions occurred in areas where people of color, particularly Black and Indigenous people, lived. In Seattle, more interventions occurred in areas where people with disabilities, on food stamps, and children lived. In Vancouver, more interventions occurred in areas where recent immigrants lived, or where people used public transit or cycled to work. Street reallocations could be opportunities for cities to redress inequities in mobility and access to public spaces. Going forward, it is imperative to monitor how cities use data and welcome communities to redesign these temporary spaces to be corridors for their own mobility.
Keywords
Covid-19; Equity; Inequalities; Built Environment; Mobility; Cities; Mobility Justice
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
Wang, Yunhong; Lee, Hyun Woo; Tang, Wenzhe; Whittington, Jan; Qiang, Maoshan. (2021). Structural Equation Modeling for the Determinants of International Infrastructure Investment: Evidence from Chinese Contractors. Journal Of Management In Engineering, 37(4).
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Abstract
International infrastructure investment can effectively accelerate infrastructure development in developing countries and thus support their social and economic progress. However, little is known of the factors that may determine the flow of international infrastructure investment to those countries. This study aims to bridge that knowledge gap, first by identifying the determinants of international infrastructure investment, and then by developing a structural equation model to reveal their underlying interrelationships. The structural equation model is applied to country-level data regarding international infrastructure investment with Chinese contractors in 141 countries worldwide over the 9-year period from 2009 to 2017. The results show that three determinants, namely infrastructure quality, labor supply, and investment interdependency, have a positive relationship with a country's international infrastructure investment inflow. However, another determinant, institutional environment, has a significantly negative impact, which suggests that when making foreign infrastructure investment, Chinese contractors enter countries with a comparatively poor institutional environment with substantial political risks. The results also highlight how much a robust infrastructure development plan can help developing countries avoid the poor-infrastructure trap, a situation in which poor infrastructure quality discourages international infrastructure investment. These research findings may assist international infrastructure investment firms to make informed decisions with regard to financing and managing projects and help policymakers who focus on attracting foreign investment in infrastructure.
Keywords
Foreign Direct-investment; Public-private Partnerships; Economic-growth; Transport Infrastructure; Developing-countries; Labor Productivity; Fit Indexes; Location; Energy; Firms; Infrastructure Investment; Institutional Environment; Infrastructure Quality; Foreign Direct Investment (fdi) Interdependency; Structure Equation Modeling; Belt And Road Initiative
Berrigan, David; Dannenberg, Andrew L.; Lee, Michelle; Rodgers, Kelly; Wojcik, Janet R.; Wali, Behram; Tribby, Calvin P.; Buehler, Ralph; Sallis, James F.; Roberts, Jennifer D.; Steedly, Ann; Peng, Binbin; Eisenberg, Yochai; Rodriguez, Daniel A. (2021). The 2019 Conference on Health and Active Transportation: Research Needs and Opportunities. International Journal Of Environmental Research And Public Health, 18(22).
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Abstract
Active transportation (AT) is widely viewed as an important target for increasing participation in aerobic physical activity and improving health, while simultaneously addressing pollution and climate change through reductions in motor vehicular emissions. In recent years, progress in increasing AT has stalled in some countries and, furthermore, the coronavirus (COVID-19) pandemic has created new AT opportunities while also exposing the barriers and health inequities related to AT for some populations. This paper describes the results of the December 2019 Conference on Health and Active Transportation (CHAT) which brought together leaders from the transportation and health disciplines. Attendees charted a course for the future around three themes: Reflecting on Innovative Practices, Building Strategic Institutional Relationships, and Identifying Research Needs and Opportunities. This paper focuses on conclusions of the Research Needs and Opportunities theme. We present a conceptual model derived from the conference sessions that considers how economic and systems analysis, evaluation of emerging technologies and policies, efforts to address inclusivity, disparities and equity along with renewed attention to messaging and communication could contribute to overcoming barriers to development and use of AT infrastructure. Specific research gaps concerning these themes are presented. We further discuss the relevance of these themes considering the pandemic. Renewed efforts at research, dissemination and implementation are needed to achieve the potential health and environmental benefits of AT and to preserve positive changes associated with the pandemic while mitigating negative ones.
Keywords
Improving Arterial Roads; Physical-activity; Cost-effectiveness; Built Environment; Autonomous Vehicles; Walking; Behavior; Impact; Active Transportation; Covid-19; Climate Change; Physical Activity; Public Health; Pandemics; Public Transportation; Collaboration; Transportation; Economic Models; Environmental Impact; Outdoor Air Quality; Vehicle Emissions; Coronaviruses; Hispanic Americans; Fatalities; Systems Analysis; African Americans; Infrastructure; Medical Research; Committees; Land Use; Economic Analysis; New Technology; United States--us
Garg, Parveen K.; Platt, Jonathan M.; Hirsch, Jana A.; Hurvitz, Philip; Rundle, Andrew; Biggs, Mary Lou; Psaty, Bruce M.; Moore, Kari; Lovasi, Gina S. (2021). Association of Neighborhood Physical Activity Opportunities with Incident Cardiovascular Disease in the Cardiovascular Health Study. Health & Place, 70.
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Abstract
We determined associations of cumulative exposures to neighborhood physical activity opportunities with risk of incident cardiovascular disease (CVD). We included 3595 participants from the Cardiovascular Health Study recruited between 1989 and 1993 (mean age = 73; 60% women; 11% black). Neighborhood environment measures were calculated using Geographic Information Systems (GIS) and annual information from the National Establishment Time Series database, including the density of (1) walking destinations and (2) physical activity/ recreational facilities in a 1- and 5-km radius around the respondent's home. Incident CVD was defined as the development of myocardial infarction, stroke, or cardiovascular death and associations with time to incident CVD were estimated using Cox proportional hazards models. A total of 1986 incident CVD cases occurred over a median follow-up of 11.2 years. After adjusting for baseline and time-varying individual and neighborhood-level confounding, a one standard deviation increase in walking destinations and physical activity/recreational facilities within 5 km of home was associated with a respective 7% (95% confidence interval (CI) = 0.87-0.99) and 12% (95% CI = 0.73-1.0) decreased risk of incident CVD. No significant associations were noted within a 1-km radius. Efforts to improve the availability of physical activity resources in neighborhoods may be an important strategy for lowering CVD.
Keywords
Cardiovascular Diseases; Physical Activity; Proportional Hazards Models; Geographic Information Systems; Recreation Centers; Built Environment; Cardiovascular Disease; Coronary-heart-disease; Census Tract Data; Older-adults; Longitudinal Associations; Risk; Resources; Time; Atherosclerosis; Survival