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Department: College of Built Environments

Deriving a Long-Term Pan Evaporation Reanalysis Dataset for Two Chinese Pan Types

Wang, Kaiwen; Liu, Xiaomang; Li, Yuqi; Yang, Xiaohua; Bai, Peng; Liu, Changming; Chen, Fei. (2019). Deriving a Long-Term Pan Evaporation Reanalysis Dataset for Two Chinese Pan Types. Journal Of Hydrology, 579.

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Abstract

A long-term continuous and consistent pan evaporation (E-pan) reanalysis dataset will augment the analysis of E-pan distributions when the observation network is discontinuous or inconsistent, and assist in the evaluation of the outputs of General Circulation Models (GCMs) and Land Surface Models (LSMs). From the 1950s to early 2000s, China had a continuous observation of the D20 pan, but this was replaced by the 601B pan across China around 2002, and thus the E-pan observation network became discontinuous and inconsistent. This study developed a long-term monthly, 0.05 degrees, continuous and consistent reanalysis dataset for both D20 and 6018 pans covering mainland China throughout 1960-2014, based on meteorological data homogenization and interpolation and E-pan assimilation. The PenPan-V3 model used inE(pan) assimilation was successfully validated by observations at 767 and 591 stations for D20 and 601B pans, respectively. Comprehensively considering the physical influence of elevation, radiation, wind speed, humidity, and air temperature, the average annual and seasonal gridded E-pan reanalyses show significant spatial dependent on proximity to the ocean and latitude, consistent with previous studies. The reanalysis dataset can be used to analyze E-pan distributions across China, including the areas without observations, and to estimate the representativeness of E-pan to atmospheric evaporative demand. The dataset has been released in two cloud servers in China and the United States, and it will continue to be maintained and updated.

Keywords

General Circulation Model; Evaporation (meteorology); Atmospheric Temperature; Wind Speed; China; Long-term Continuous And Consistent Dataset; Pan Evaporation Reanalysis Dataset; Representativeness To Atmospheric Evaporative Demand; Maximal T-test; Reference Evapotranspiration; Climate Data; Energy-balance; Reference Crop; Trends; Water; Model; Demand; General Circulation Models; Air Temperature; Data Collection; Evaporation; Evaporative Demand; Humidity; Latitude; Meteorological Data; United States

Participatory Infrastructures: The Politics of Mobility Platforms

Dunn, Peter T. (2020). Participatory Infrastructures: The Politics of Mobility Platforms. Urban Planning, 5(4), 335 – 346.

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Abstract

Much of everyday life in cities is now mediated by digital platforms, a mode of organization in which control is both distributed widely among participants and sharply delimited by the platform's constraints. This article uses examples of smartphone-based platforms for urban mobility to argue that platforms create new political arrangements of the city, intermediating the social processes of management and movement that characterize urban life. Its empirical basis is a study of user interfaces, data specifications, and algorithms used in the operation and regulation of ride-hailing services and bike-share systems. I focus on three aspects of urban politics affected by platforms: its location, its participants, and the types of conflict it addresses. First, the programming forums in which decisions are encoded in and distributed through platforms' core digital architecture are new sites of policy deliberation outside the more familiar arenas of city politics. Second, travelers have new opportunities to use platforms for travel on their own terms, but this expanded participation is circumscribed by interfaces that presuppose individual, transactional engagement rather than a participation attentive to a broader social and environmental context. Finally, digital systems show themselves to be well suited to enforcing quantifiable distributional goals, but struggle to resolve the more nuanced relational matters that constitute the politics of everyday city life. These illustrations suggest that digital tools for managing transportation are not only political products, but also reset the stage on which urban encounters play out.

Keywords

Construction; Users; Digital Geographies; Infrastructure; Participation; Platform Urbanism; Shared-use Mobility

Moving Toward Physical Activity Targets by Walking to Transit: National Household Transportation Survey, 2001-2017

Le, Vi T.; Dannenberg, Andrew L. (2020). Moving Toward Physical Activity Targets by Walking to Transit: National Household Transportation Survey, 2001-2017. American Journal Of Preventive Medicine, 59(3), E115 – E123.

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Abstract

Introduction: Public transportation systems can help people engage in physical activity. This study assesses sociodemographic correlates and trends in the daily time spent walking to and from transit in the U.S. from 2001 to 2017. Methods: This cross-sectional study used data from the 2001, 2009, and 2017 National Household Transportation Survey. Data were analyzed in 2019 to assess the daily level of physical activity attained solely by walking to and from transit. Regression models were used to examine predictors of daily transit-associated walking. Results: Compared with the full National Household Transportation Survey sample, transit users who walked to and from transit tended to be younger, from households earning <$25,000 per year, in areas with rail infrastructure, and did not have a household-owned car. Transit walkers spent a median of 20 minutes per day (95% CI=18.5, 21.5) walking to and from transit in 2017, compared with a median of 19 minutes (95% CI=17.5, 20.5) in 2001. Among transit walkers, daily transitassociated physical activity was 27% higher for those residing in areas with rail infrastructure (adjusted coefficient=1.27, 95% CI=1.11, 1.46) and 34% higher for those from households earning $99,999 per year (adjusted coefficient=1.34, 95% CI=1.15, 1.56). Conclusions: As documented in a growing literature, most public transit trips include at least some walking; thus, efforts to encourage transit use are favorable to public health. Continued monitoring by transportation surveys is important as new forms of mobility and changing demographics may impact future transit use and associated physical activity. (C) 2020 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Keywords

Physical Activity; Household Surveys; Public Transit; Cross-sectional Method; Public Health; Walking; Exercise; Research Funding; Transportation; Replacing Sedentary Time; Public-transit; Travel; Mortality; Adults; Health; Work

The Ecological and Evolutionary Consequences of Systemic Racism in Urban Environments

Schell, Christopher J.; Dyson, Karen; Fuentes, Tracy L.; Des Roches, Simone; Harris, Nyeema C.; Miller, Danica Sterud; Woelfle-Erskine, Cleo A.; Lambert, Max R. (2020). The Ecological and Evolutionary Consequences of Systemic Racism in Urban Environments. Science, 369(6510), 1446.

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Abstract

Urban areas are dynamic ecological systems defined by interdependent biological, physical, and social components. The emergent structure and heterogeneity of urban landscapes drives biotic outcomes in these areas, and such spatial patterns are often attributed to the unequal stratification of wealth and power in human societies. Despite these patterns, few studies have effectively considered structural inequalities as drivers of ecological and evolutionary outcomes and have instead focused on indicator variables such as neighborhood wealth. In this analysis, we explicitly integrate ecology, evolution, and social processes to emphasize the relationships that bind social inequities-specifically racism-and biological change in urbanized landscapes. We draw on existing research to link racist practices, including residential segregation, to the heterogeneous patterns of flora and fauna observed by urban ecologists. In the future, urban ecology and evolution researchers must consider how systems of racial oppression affect the environmental factors that drive biological change in cities. Conceptual integration of the social and ecological sciences has amassed considerable scholarship in urban ecology over the past few decades, providing a solid foundation for incorporating environmental justice scholarship into urban ecological and evolutionary research. Such an undertaking is necessary to deconstruct urbanization's biophysical patterns and processes, inform equitable and anti-racist initiatives promoting justice in urban conservation, and strengthen community resilience to global environmental change.

Keywords

New-york; Climate-change; Land-cover; Socioeconomic-status; Ecosystem Services; Oxidative Stress; Green Spaces; Gene Flow; Justice; Cities

Differential Associations of the Built Environment on Weight Gain by Sex and Race/Ethnicity but Not Age

Buszkiewicz, James H.; Bobb, Jennifer F.; Kapos, Flavia; Hurvitz, Philip M.; Arterburn, David; Moudon, Anne Vernez; Cook, Andrea; Mooney, Stephen J.; Cruz, Maricela; Gupta, Shilpi; Lozano, Paula; Rosenberg, Dori E.; Theis, Mary Kay; Anau, Jane; Drewnowski, Adam. (2021). Differential Associations of the Built Environment on Weight Gain by Sex and Race/Ethnicity but Not Age. International Journal Of Obesity, 45(12), 2648 – 2656.

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Abstract

Objective To explore the built environment (BE) and weight change relationship by age, sex, and racial/ethnic subgroups in adults. Methods Weight trajectories were estimated using electronic health records for 115,260 insured Kaiser Permanente Washington members age 18-64 years. Member home addresses were geocoded using ArcGIS. Population, residential, and road intersection densities and counts of area supermarkets and fast food restaurants were measured with SmartMaps (800 and 5000-meter buffers) and categorized into tertiles. Linear mixed-effect models tested whether associations between BE features and weight gain at 1, 3, and 5 years differed by age, sex, and race/ethnicity, adjusting for demographics, baseline weight, and residential property values. Results Denser urban form and greater availability of supermarkets and fast food restaurants were associated with differential weight change across sex and race/ethnicity. At 5 years, the mean difference in weight change comparing the 3rd versus 1st tertile of residential density was significantly different between males (-0.49 kg, 95% CI: -0.68, -0.30) and females (-0.17 kg, 95% CI: -0.33, -0.01) (P-value for interaction = 0.011). Across race/ethnicity, the mean difference in weight change at 5 years for residential density was significantly different among non-Hispanic (NH) Whites (-0.47 kg, 95% CI: -0.61, -0.32), NH Blacks (-0.86 kg, 95% CI: -1.37, -0.36), Hispanics (0.10 kg, 95% CI: -0.46, 0.65), and NH Asians (0.44 kg, 95% CI: 0.10, 0.78) (P-value for interaction <0.001). These findings were consistent for other BE measures. Conclusion The relationship between the built environment and weight change differs across demographic groups. Careful consideration of demographic differences in associations of BE and weight trajectories is warranted for investigating etiological mechanisms and guiding intervention development.

Keywords

Body-mass Index; Socioeconomic-status; Food Environment; Obesity; Health; Outcomes; Scale; Risk; Minority & Ethnic Groups; Urban Environments; Etiology; Demographics; Sex; Residential Density; Supermarkets; Age; Race; Ethnicity; Property Values; Body Weight Gain; Electronic Medical Records; Fast Food; Electronic Health Records; Real Estate; Subgroups; Demography; Trajectory Analysis; Weight

A Simulation-Based Dynamic Scheduling Model for Curtain Wall Production Considering Construction Planning Reliability

Kim, Taehoon; Kim, Yong-Woo; Cho, Hunhee. (2021). A Simulation-Based Dynamic Scheduling Model for Curtain Wall Production Considering Construction Planning Reliability. Journal Of Cleaner Production, 286.

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Abstract

Appropriate production scheduling of curtain wall systems is essential for the successful completion of construction projects. The construction process of the curtain wall system is mainly on the critical path and accounts for 10-15% of the total construction cost. Should curtain wall products not be timeously delivered to the construction site, construction projects are likely to fall behind schedule with most relevant activities on curtainwall installation on a critical path. However, due-date uncertainty caused by a contractor's lack of planning reliability causes the curtain wall production schedule to become complex and changes the due date after the initial order. In this regard, this study proposes a discrete event simulation-based dynamic scheduling model for curtain wall production to deliver products on time to the construction site by considering each construction project's planning reliability. Through simulation experiments, the validity and effectiveness of the proposed model were tested. The results of this study will help the successful completion of construction projects by ensuring the progress of the curtain wall system construction and follow-up activities following the construction schedule. (C) 2020 Elsevier Ltd. All rights reserved.

Keywords

Construction Industry; Discrete Event Simulation; Dynamic Scheduling; Production Control; Production Planning; Project Management; Reliability; Scheduling; Walls; Construction Planning Reliability; Construction Schedule; Curtain Wall System Construction; Construction Project; Discrete Event Simulation-based Dynamic Scheduling Model; Curtain Wall Production Schedule; Curtain Wall Installation; Curtain Wall Products; Total Construction Cost; Critical Path; Production Scheduling; Off-site Construction; Demand Variability; Job Shops; Precast; Minimize; Number; Curtain Wall; Simulation; Planning Reliability; Dispatching Rule

Structural Equation Modeling for the Determinants of International Infrastructure Investment: Evidence from Chinese Contractors

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

Hygrothermal Behavior Of Post-retrofit Housing: A Review Of The Impacts Of The Energy Efficiency Upgrade Strategies.

Recart, Carolina; Dossick, Carrie Sturts. (2022). Hygrothermal Behavior Of Post-retrofit Housing: A Review Of The Impacts Of The Energy Efficiency Upgrade Strategies. Energy & Buildings, 262.

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Abstract

Improving energy efficiency of existing buildings is currently among the most diverse and extensive mitigation opportunities to reduce energy consumption and CO2 emissions worldwide. However, the implementation of energy-saving measures has caused unintended impacts, often correlated with dampness and mold growth connected to poor hygrothermal behavior in residential buildings. The focus of this paper is research on the impacts of energy efficiency measures (EEMs) in regard to the hygrothermal behavior resulting from the interaction of building's envelope, indoor environment, and occupants. The results show that dampness and mold growth are by no means exclusive to neglected houses, since the occurrence of these pathologies actually depends upon a complex set of conditions, including indoor and outdoor conditions, occupancy, maintenance, ventilation, mechanical systems, and quality of the envelope. We found that building envelope post-retrofit may suffer from higher levels of moisture and dampness, higher condensations risks, and a faster structural degradation caused by higher humidity levels. We also found that measuring hygrothermal behavior may play a role in more accurately predicting both overall energy consumption and occupant comfort. While hygrothermal behavior may be problematic, we found evidence that retrofits may moderately improve thermal comfort. (c) 2022 Elsevier B.V. All rights reserved.

Keywords

Energy Consumption; Energy Consumption Of Buildings; Carbon Emissions; Geothermal Ecology; Housing; Thermal Comfort; Building Envelopes; Dampness And Mold; Energy Retrofits; Hygrothermal Behavior; Residential Buildings; Unintended Impacts; Indoor Air-quality; Low-income; Environmental-quality; Assistance-program; Building Envelope; Health; Ventilation; Weatherization; Performance; Mold Growths; Indoor Environments; Moisture Effects; Energy Efficiency; Residential Areas; Mechanical Systems; Moisture Content; Green Buildings; Energy Conservation; Carbon Dioxide; Mold; Emission Measurements; Emissions; Mitigation; Buildings; Occupancy; Retrofitting; Mechanical Properties

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

Terrestrial Carbon Stocks across a Gradient of Urbanization: A Study of the Seattle, WA Region

Hutyra, Lucy R.; Yoon, Byungman; Alberti, Marina. (2011). Terrestrial Carbon Stocks across a Gradient of Urbanization: A Study of the Seattle, WA Region. Global Change Biology, 17(2), 783 – 797.

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Abstract

Most of our global population and its CO2 emissions can be attributed to urban areas. The process of urbanization changes terrestrial carbon stocks and fluxes, which, in turn, impact ecosystem functions and atmospheric CO2 concentrations. Using the Seattle, WA, region as a case study, this paper explores the relationships between aboveground carbon stocks and land cover within an urbanizing area. The major objectives were to estimate aboveground live and dead terrestrial carbon stocks across multiple land cover classes and quantify the relationships between urban cover and vegetation across a gradient of urbanization. We established 154 sample plots in the Seattle region to assess carbon stocks as a function of distance from the urban core and land cover [urban (heavy, medium, and low), mixed forest, and conifer forest land covers]. The mean (and 95% CI) aboveground live biomass for the region was 89 +/- 22 Mg C ha-1 with an additional 11.8 +/- 4 Mg C ha-1 of coarse woody debris biomass. The average live biomass stored within forested and urban land covers was 140 +/- 40 and 18 +/- 14 Mg C ha-1, respectively, with a 57% mean vegetated canopy cover regionally. Both the total carbon stocks and mean vegetated canopy cover were surprisingly high, even within the heavily urbanized areas, well exceeding observations within other urbanizing areas and the average US forested carbon stocks. As urban land covers and populations continue to rapidly increase across the globe, these results highlight the importance of considering vegetation in urbanizing areas within the terrestrial carbon cycle.

Keywords

Urbanization & The Environment; Carbon Cycle; Carbon In Soils; Climate Change Prevention; Population & The Environment; Land Cover; Cities & Towns -- Environmental Conditions; Seattle (wash.); Washington (state); Climate Change; Development; Mitigation; Pacific Northwest; Urban; United-states; Woody Debris; Storage; Growth; Responses; Fluxes; Co2; Sequestration; Landscape; Forests