Van Den Wymelenberg, Kevin; Inanici, Mehlika; Johnson, Peter. (2010). The Effect of Luminance Distribution Patterns on Occupant Preference in a Daylit Office Environment. Leukos, 7(2), 103 – 122.
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Abstract
New research in daylighting metrics and developments in validated digital High Dynamic Range (HDR) photography techniques suggest that luminance based lighting controls have the potential to provide occupant satisfaction and energy saving improvements over traditional illuminance based lighting controls. This paper studies occupant preference and acceptance of patterns of luminance using HDR imaging and a repeated measures design methodology in a daylit office environment. Three existing luminance threshold analysis methods [method1: predetermined absolute luminance threshold (for example, 2000 cd/m(2)), method2: scene based mean luminance threshold, and method3: task based mean luminance threshold] were studied along with additional candidate metrics for their ability to explain luminance variability of 18 participant assessments of 'preferred' and 'just disturbing' scenes under daylighting conditions. Per-pixel luminance data from each scene were used to calculate Daylighting Glare Probability (DGP), Daylight Glare Index (DGI), and other candidate metrics using these three luminance threshold analysis methods. Of the established methods, the most consistent and effective metrics to explain variability in subjective responses were found to be; mean luminance of the task (using method3; (adj)r(2) = 0.59), mean luminance of the entire scene (using method2; (adj)r(2) = 0.44), and DGP using 2000 cd/m(2) as a glare source identifier (using method1; (adj)r(2) = 0.41). Of the 150 candidate metrics tested, the most effective was the 'mean luminance of the glare sources', where the glare sources were identified as 7* the mean luminance of the task position ((adj)r(2) = 0.64). Furthermore, DGP consistently performed better than DGI, confirming previous findings. 'Preferred' scenes never had more than similar to 10 percent of the field of view (FOV) that exceeded 2000 cd/m(2). Standard deviation of the entire scene luminance also proved to be a good predictor of satisfaction with general visual appearance.
Keywords
Glare; Daylight Metrics; Luminance Based Lighting Controls; Discomfort Glare; Occupant Preference; High Dynamic Range
Hong, E-Sok Andy; Bae, Christine. (2012). Exposure of Bicyclists to Air Pollution in Seattle, Washington Hybrid Analysis Using Personal Monitoring and Land Use Regression. Transportation Research Record, 2270, 59 – 66.
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Abstract
The increase in urban bicycling facilities, raises public health concerns for potential exposure of bicyclists to traffic emissions. For an assessment of bicyclists' exposure to local traffic emissions, a hybrid approach is presented; it combines personal monitoring and a land use regression (LUR) model. Black carbon, a proxy variable for traffic-related air pollution, was measured with an Aethalometer along the predesignated bicycle route in Seattle, Washington, for 10 days, during a.m. and p.m. peak hours (20 sampling campaigns). Descriptive statistics and three-dimensional pollution maps were used to explore temporal variations and to identify pollution hot spots. The LUR model was developed to quantify the influence of spatial covariates on black carbon concentrations along the designated route. The results indicated that the black carbon concentrations fluctuated throughout the sampling periods and showed statistically significant diurnal and monthly patterns. The hot spot analysis suggests that proximity to traffic and other physical environments have important impacts on bicyclists' exposure and demand further investigation on the localized effects of traffic emissions on exposure levels. The LUR model explains 46% of the variations in black carbon concentrations, and significant relationships are found with types of bicycle route facility, wind speed, length of truck routes, and transportation and utility land uses. This research is the first application of the LUR approach in quantifying bicyclists' exposure to air pollution in transport microenvironments. This study provides a rationale for encouraging municipalities to develop effective strategies to mitigate the health risks of exposure to local traffic emissions in complex urban bicycling environments.
Keywords
Particulate Matter; Diesel Exhaust; Health; Model; Particles; Asthma; City
Armbruster, Ginger; Endicott-Popovsky, Barbara; Whittington, Jan. (2013). Threats to Municipal Information Systems Posed by Aging Infrastructure. International Journal Of Critical Infrastructure Protection, 6(3-4), 123 – 131.
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Abstract
State and local governments across the United States are leveraging the Internet and associated technologies to dramatically change the way they offer public services. While they are motivated to capture efficiencies, the public entities increasingly rely on information systems that are dependent on energy and related civil structures. This reliance is incongruous with the widespread awareness of aging infrastructure - decaying for lack of investment - in cities across the United States. Important questions that come up in this environment of persistent expansion of the use of digital assets are the following: What threat does aging infrastructure pose to governmental reliance on computing infrastructures? How are local governments responding to this threat? Are the solutions posed appropriate to the problem, or do they pose new and different threats? This paper uses a case involving the disruption of a local government data center due to the failure of an electrical bus to illustrate how the threats of aging infrastructure grow, quietly and steadily, into emergencies, on par with the catastrophic events encountered in the context of critical infrastructure protection. The decisions precipitating the disruption are routine, borne of circumstances shared by agencies that are pressed to maintain services with scarce resources. Patterns of capital investment and management explain the emergence of crises in routine operations. If, as in the case described in this paper, deferred maintenance motivates public agents to explore private cloud services, then governments may solve several problems, but may also be exposed to new risks as they enter into arrangements from which they are unable to exit. (C) 2013 Elsevier B.V. All rights reserved.
Keywords
Aging Infrastructure; Municipal Data Center; Capital Improvement; Interdependence
Perry, Cynthia K.; Herting, Jerald R.; Berke, Ethan M.; Nguyen, Huong Q.; Moudon, Anne Vernez; Beresford, Shirley A. A.; Ockene, Judith K.; Manson, Joann E.; Lacroix, Andrea Z. (2013). Does Neighborhood Walkability Moderate the Effects of Intrapersonal Characteristics on Amount of Walking in Post-Menopausal Women? Health & Place, 21, 39 – 45.
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Abstract
This study identifies factors associated with walking among postmenopausal women and tests whether neighborhood walkability moderates the influence of intrapersonal factors on walking. We used data from the Women's Health Initiative Seattle Center and linear regression models to estimate associations and interactions. Being white and healthy, having a high school education or beyond and greater non-walking exercise were significantly associated with more walking. Neighborhood walkability was not independently associated with greater walking, nor did it moderate influence of intrapersonal factors on walking. Specifying types of walking (e.g., for transportation) can elucidate the relationships among intrapersonal factors, the built environment, and walking. (C) 2013 Elsevier Ltd. All rights reserved.
Keywords
Self-talk; Postmenopause; Walking; Women's Health; Built Environment; Social Interaction; Regression Analysis; Postmenopausal Women; Walkability; Physical-activity; Older-adults; United-states; Us Adults; Exercise; Obesity; Transportation; Association; Attributes
Duncan, Glen E.; Mills, Brianna; Strachan, Eric; Hurvitz, Philip; Huang, Ruizhu; Moudon, Anne Vernez; Turkheimer, Eric. (2014). Stepping Towards Causation in Studies of Neighborhood and Environmental Effects: How Twin Research Can Overcome Problems of Selection and Reverse Causation. Health & Place, 27, 106 – 111.
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Abstract
No causal evidence is available to translate associations between neighborhood characteristics and health outcomes into beneficial changes to built environments. Observed associations may be causal or result from uncontrolled confounds related to family upbringing. Twin designs can help neighborhood effects studies overcome selection and reverse causation problems in specifying causal mechanisms. Beyond quantifying genetic effects (i.e., heritability coefficients), we provide examples of innovative measures and analytic methods that use twins as quasi-experimental controls for confounding by environmental effects. We conclude that collaboration among investigators from multiple fields can move the field forward by designing studies that step toward causation. (C) 2014 Elsevier Ltd. All rights reserved,
Keywords
Residential Location; Methylation; Gene; Interplay; Obesity; Causality; Environment Design; Lifestyle Risk Reduction; Social And Built Environments; Twin Studies
Purcell, Mark. (2014). Possible Worlds: Henri Lefebvre and the Right to the City. Journal Of Urban Affairs, 36(1), 141 – 154.
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Abstract
There has been much attention paid recently the idea of the right to the city. This article argues that in order to fully appreciate the power of the idea, we should understand it through a close reading of Henri Lefebvre's body of work on the city and politics. Lefebvre presents a radical vision for a city in which users manage urban space for themselves, beyond the control of both the state and capitalism. However, while it calls for profound change, Lefebvre's vision is also eminently practical; it can very much serve as a guide and inspiration for concrete action to change the city today.
Dossick, Carrie Sturts; Anderson, Anne; Azari, Rahman; Iorio, Josh; Neff, Gina; Taylor, John E. (2015). Messy Talk in Virtual Teams: Achieving Knowledge Synthesis through Shared Visualizations. Journal Of Management In Engineering, 31(1).
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Abstract
Engineering teams collaborating in virtual environments face many technical, social, and cultural challenges. In this paper we focus on distributed teams making joint unanticipated discoveries in virtual environments. We operationalize a definition of messy talk as a process in which teams mutually discover issues, critically engage in clarifying and finding solutions to the discovered issues, exchange their knowledge, and resolve the issue. Can globally distributed teams use messy talk via virtual communication technology? We analyzed the interactions of four distributed student teams collaborating on a complex design and planning project using building information models (BIMs) and the cyber-enabled global research infrastructure for design (CyberGRID), a virtual world specifically developed for collaborative work. Their interactions exhibited all four elements of messy talk, even though resolution was the least common. Virtual worlds support real-time joint problem solving by (1)providing affordances for talk mediated by shared visualizations, (2)supporting team perceptions of building information models that are mutable, and (3)allowing transformations of those models while people were together in real time. Our findings suggest that distributed team collaboration requires technologies that support messy talkand iterative trial and errorfor complex multidimensional problems. (C) 2014 American Society of Civil Engineers.
Keywords
Buildings (structures); Data Visualisation; Design; Grid Computing; Groupware; Knowledge Management; Structural Engineering Computing; Team Working; Virtual Manufacturing; Virtual Reality; Virtual Teams; Knowledge Synthesis; Engineering Teams Collaboration; Virtual Environments; Technical Challenges; Social Challenges; Cultural Challenges; Distributed Teams Making; Messy Talk; Knowledge Exchange; Globally Distributed Teams; Virtual Communication Technology; Distributed Student Teams; Design And Planning Project; Building Information Models; Bim; Cyber-enabled Global Research Infrastructure; Cybergrid; Virtual World; Collaborative Work; Team Perceptions; Iterative Trial And Error; Complex Multidimensional Problems; Visual Representations; Construction; Technology; Implementation; Collaboration; Communication; Teamwork; Digital Techniques; Knowledge-based Systems
Wilson, A. Meriwether W.; Mugerauer, Robert; Klinger, Terrie. (2015). Rethinking Marine Infrastructure Policy and Practice: Insights from Three Large-Scale Marina Developments in Seattle. Marine Policy, 53, 67 – 82.
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Abstract
The global transformation of the marine nearshore is generating profound losses of ecological and geomorphological functions and ecosystem services, as natural environments are replaced with built. With conservation a diminishing option and restoration often unrealistic, there is a need to rethink development and the potential for marine infrastructure to contribute to net environmental gain. Through analysis of 150 years of change associated with the development of three large-scale marinas in the Seattle area, this research identifies the ways in which evolving policy frameworks and ecological understanding determine the nature, efficiency and environmental outcomes of coastal marine developments. Decisions on infrastructure design, mitigation strategies and policy interpretations directly determined the ecological fate of marine biota inhabiting these structures as well as surrounding ecosystems. In spite of increasing evidence of environmental legislation driving mitigation and innovative engineering, the net ecological trajectories remained negative. There were no tested demonstrations of marine mitigation to confirm which measures would succeed. Where scientific understanding existed, the uptake into planning and legislation was slow. More broadly, this research highlights a need and opportunity to consider marine infrastructure as living laboratories to inform a policy shift from a no-net-loss paradigm to net-environmental-gain. This evolution is timely, with sea level rise requiring new approaches to coastal defenses and with marine energy infrastructure increasingly being located offshore, where there is little knowledge of the ecological changes occurring in both time and space. (C) 2014 Elsevier Ltd. All rights reserved.
Keywords
Coastal; Restoration; Landscape; Habitats; Science; Driver; Areas; Act; Marine Coastal Infrastructure; Ecological Mitigation; Novel Marine Habitats; Environmental Governance; Pacific Northwest
El-Anwar, Omar; Ye, Jin; Orabi, Wallied. (2016). Innovative Linear Formulation for Transportation Reconstruction Planning. Journal Of Computing In Civil Engineering, 30(3).
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Abstract
Following disasters, the pace of restoring transportation networks can have a significant impact on economic and societal recovery. However, reconstruction and repair efforts are typically faced by budget constraints that require careful selection among competing contractors. This paper presents an innovative formulation to optimize this complex planning problem in order to maximize the rate of transportation network recovery while minimizing the associated reconstruction costs. This study first contributes to the body of knowledge by offering an effective and efficient means of identifying the optimal schedules for reconstruction projects and the optimal contractor assignments. This is achieved by solving the problem using a new mixed-integer linear programming model. However, there are four main formulation challenges to represent this problem using linear equations because of the need to use logical operators. As such, the second contribution of this study is in offering innovative solutions to overcome these formulation challenges, which are generalizable to other construction scheduling and planning problems. This paper is companion to another paper that describes a holistic optimization and traffic assessment methodology for post-disaster reconstruction planning for damaged transportation networks. (C) 2015 American Society of Civil Engineers.
Keywords
Integer Programming; Linear Programming; Transportation; Innovative Linear Formulation; Transportation Reconstruction Planning; Economic Recovery; Societal Recovery; Complex Planning Problem; Transportation Network Recovery; Mixed-integer Linear Programming Model; Traffic Assessment Methodology; Postdisaster Reconstruction Planning; Natural Disasters; Housing Projects; Construction; Optimization; Performance; Robustness; Earthquake; Efficiency; Recovery; Plans; Transportation Network Reconstruction; Post-disaster Recovery; Multi-objective Optimization; Mixed-integer Linear Programming; Contractors Assignment; Linear Formulation; Reconstruction Costs
McPhearson, Timon; Pickett, Steward T. A.; Grimm, Nancy B.; Niemela, Jari; Alberti, Marina; Elmqvist, Thomas; Weber, Christiane; Haase, Dagmar; Breuste, Juergen; Qureshi, Salman. (2016). Advancing Urban Ecology toward a Science of Cities. Bioscience, 66(3), 198 – 212.
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Abstract
Urban ecology is a field encompassing multiple disciplines and practical applications and has grown rapidly. However, the field is heterogeneous as a global inquiry with multiple theoretical and conceptual frameworks, variable research approaches, and a lack of coordination among multiple schools of thought and research foci. Here, we present an international consensus on how urban ecology can advance along multiple research directions. There is potential for the field to mature as a holistic, integrated science of urban systems. Such an integrated science could better inform decisionmakers who need increased understanding of complex relationships among social, ecological, economic, and built infrastructure systems. To advance the field requires conceptual synthesis, knowledge and data sharing; cross-city comparative research, new intellectual networks, and engagement with additional disciplines. We consider challenges and opportunities for understanding dynamics of urban systems. We suggest pathways for advancing urban ecology research to support the goals of improving urban sustainability and resilience, conserving urban biodiversity, and promoting human well-being on an urbanizing planet.
Keywords
Urban Ecology (biology); Urban Biodiversity; Urbanization & The Environment; Life Sciences; Medical Sciences; Comparative Research; Complexity; Conceptual Frameworks; Urban Ecology; Urban Systems; Ecosystem Services; Green Spaces; Resilience; Framework; Systems; Design; Water; Tree