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Department: Urban Design and Planning

Built Environment Effects on Bike Crash Frequency and Risk in Beijing

Chen, Peng; Sun, Feiyang; Wang, Zhenbo; Gao, Xu; Jiao, Junfeng; Tao, Zhimin. (2018). Built Environment Effects on Bike Crash Frequency and Risk in Beijing. Journal Of Safety Research, 64, 135 – 143.

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Abstract

Introduction: Building a safe biking environment is crucial to encouraging bicycle use. In developed areas with higher density and more mixed land use, the built environment factors that pose a crash risk may vary. This study investigates the connection between biking risk factors and the compact built environment, using data for Beijing. Method: In the context of China, this paper seeks to answer two research questions. First, what types of built environment factors are correlated with bike-automobile crash frequency and risk? Second, how do risk factors vary across different types of bikes? Poisson lognormal random effects models are employed to examine how land use and roadway design factors are associated with the bike-automobile crashes. Results: The main findings are: (1) bike-automobile crashes are more likely to occur in densely developed areas, which is characterized by higher population density, more mixed land use, denser roads and junctions, and more parking lots; (2) areas with greater ground transit are correlated with more bike-automobile crashes and higher risks of involving in collisions; (3) the percentages of wider streets show negative associations with bike crash frequency; (4) built environment factors cannot help explain factors contributing to motorcycle-automobile crashes. Practical Applications: In China's dense urban context, important policy implications for bicycle safety improvement drawn from this study include: prioritizing safety programs in urban centers, applying safety improvements to areas with more ground transit, placing bike-automobile crash countermeasures at road junctions, and improving bicycle safety on narrower streets. (C) 2018 National Safety Council and Elsevier Ltd. All rights

Keywords

Motorcycling Accidents; Built Environment; Motorcycling; Poisson Distribution; Safety; Beijing (china); Bike-automobile Crash; Frequency; Poisson Lognormal Random Effects Model; Risk; Signalized Intersections; Transportation Modes; Urban Intersections; Bicycle Crashes; Motor-vehicle; Riders; Infrastructure; China; Severity; Frequency Distribution; Risk Factors; Bicycles; Fatalities; Collisions; Traffic Accidents; Safety Programs; Urban Environments; Traffic Safety; Population Density; Crashes; Streets; Environmental Effects; Environmental Engineering; Roads; Land Use; Risk Analysis; Urban Areas; Road Design; Construction; Ecological Risk Assessment; Design Factors; Motorcycles; Urban Transportation; Studies; Safety Management; Beijing China

Development of a Regional Lidar-Derived Above-Ground Biomass Model with Bayesian Model Averaging for Use in Ponderosa Pine and Mixed Conifer Forests in Arizona and New Mexico, USA

Tenneson, Karis; Patterson, Matthew S.; Mellin, Thomas; Nigrelli, Mark; Joria, Peter; Mitchell, Brent. (2018). Development of a Regional Lidar-Derived Above-Ground Biomass Model with Bayesian Model Averaging for Use in Ponderosa Pine and Mixed Conifer Forests in Arizona and New Mexico, USA. Remote Sensing, 10(3).

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Abstract

Historical forest management practices in the southwestern US have left forests prone to high-severity, stand-replacement fires. Reducing the cost of forest-fire management and reintroducing fire to the landscape without negative impact depends on detailed knowledge of stand composition, in particular, above-ground biomass (AGB). Lidar-based modeling techniques provide opportunities to increase ability of managers to monitor AGB and other forest metrics at reduced cost. We developed a regional lidar-based statistical model to estimate AGB for Ponderosa pine and mixed conifer forest systems of the southwestern USA, using previously collected field data. Model selection was performed using Bayesian model averaging (BMA) to reduce researcher bias, fully explore the model space, and avoid overfitting. The selected model includes measures of canopy height, canopy density, and height distribution. The model selected with BMA explains 71% of the variability in field-estimates of AGB, and the RMSE of the two independent validation data sets are 23.25 and 32.82 Mg/ha. The regional model is structured in accordance with previously described local models, and performs equivalently to these smaller scale models. We have demonstrated the effectiveness of lidar for developing cost-effective, robust regional AGB models for monitoring and planning adaptively at the landscape scale.

Keywords

Laser Scanner Data; Landscape Restoration Program; Canopy Fuel Parameters; Discrete-return Lidar; Western United-states; Wave-form Lidar; Airborne Laser; Tropical Forest; Climate-change; Adaptive Management; Forest Biomass; Aboveground Biomass; Airborne Lidar; Monitoring; Regional Forest Inventory; Variable Selection; Bayesian Model Averaging; Multiple Linear Regression

Framing the Question: Is Shrinking Good or Bad?

Moudon, Anne Vernez. (2019). Framing the Question: Is Shrinking Good or Bad? Journal Of Urban Design, 24(1), 66 – 68.

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Keywords

Urban Planning; Unemployment; Cost Of Living; Balance Of Trade; Medical Care; Economic Development; Demography; Decision Making; Framing

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

Motorcycle Taxi Programme Increases Safe Riding Behaviours Among Its Drivers In Kampala, Uganda

Muni, Kennedy; Kobusingye, Olive; Mock, Charles; Hughes, James P.; Hurvitz, Philip M.; Guthrie, Brandon. (2020). Motorcycle Taxi Programme Increases Safe Riding Behaviours Among Its Drivers In Kampala, Uganda. Injury Prevention, 26(1), 5 – 11.

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Abstract

Background SafeBoda is a motorcycle taxi company that provides road safety training and helmets to its drivers in Kampala, Uganda. We sought to determine whether SafeBoda drivers are more likely to engage in safe riding behaviours than regular drivers (motorcycle taxi drivers not part of SafeBoda). Methods We measured riding behaviours in SafeBoda and regular drivers through: (1) computer-assisted personal interview (CAPI), where 400 drivers were asked about their riding behaviours (eg, helmet and mobile phone use) and (2) roadside observation, where riding behaviours were observed in 3000 boda-boda drivers and their passengers along major roads in Kampala. Results Across the two cross-sectional studies, a higher proportion of SafeBoda drivers than regular drivers engaged in safe riding behaviours. For instance, helmet use among SafeBoda compared with regular drivers was 21% points higher (95% CI 0.15 to 0.27; p<0.001) based on the CAPI and 45% points higher (95% CI 0.43 to 0.47; p<0.001) based on roadside observation. Furthermore, compared with regular drivers, SafeBoda drivers were more likely to report having a driver's license (66.3% vs 33.5 %; p<0.001) and a reflective jacket (99.5% vs 50.5 %; p<0.001) and were less likely to report driving towards oncoming traffic (4% vs 45.7 %; p<0.001) in the past 30 days. Conclusion The SafeBoda programme is associated with increased safe riding behaviours among motorcycle taxi drivers in Kampala. Therefore, the promotion and expansion of such programmes may lead to a reduction in morbidity and mortality due to road injuries.

Keywords

Multiple-imputation; Helmet Use; Knowledge; Injuries; Riders

Not Quite a Block Party: Covid-19 Street Reallocation Programs in Seattle, WA and Vancouver, BC

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

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

Intermetropolitan Comparison of Transportation Accessibility: Sorting Out Mobility and Proximity in San Francisco And Washington, DC

Grengs, Joe; Levine, Jonathan; Shen, Qing; Shen, Qingyun. (2010). Intermetropolitan Comparison of Transportation Accessibility: Sorting Out Mobility and Proximity in San Francisco And Washington, DC. Journal Of Planning Education And Research, 29(4), 427 – 443.

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Abstract

Both mobility and proximity influence transportation accessibility, but they exist in tension with each other. To understand the region-level trade-off between mobility and proximity requires intermetropolitan comparisons of accessibility. With a focus on the two metropolitan cases of San Francisco and Washington, D.C., we first describe a method for comparing regional accessibility and then explain a method that separates out the effects of mobility and proximity on regional accessibility. We find that the San Francisco region enjoys an accessibility advantage over Washington largely because of faster highway speeds but that central Washington offers an advantage in proximity.

Keywords

Spatial Interaction; Employment; Location; Access; Sprawl; Land Use; Methods; Nonwork Travel; Transportation; Urban Form; Regional Accessibility

Obesity and Supermarket Access: Proximity or Price?

Drewnowski, Adam; Aggarwal, Anju; Hurvitz, Philip M.; Monsivais, Pablo; Moudon, Anne V. (2012). Obesity and Supermarket Access: Proximity or Price? American Journal Of Public Health, 102(8), e74 – e80.

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Abstract

Objectives. We examined whether physical proximity to supermarkets or supermarket price was more strongly associated with obesity risk. Methods. The Seattle Obesity Study (SOS) collected and geocoded data on home addresses and food shopping destinations for a representative sample of adult residents of King County, Washington. Supermarkets were stratified into 3 price levels based on average cost of the market basket. Sociodemographic and health data were obtained from a telephone survey. Modified Poisson regression was used to test the associations between obesity and supermarket variables. Results. Only 1 in 7 respondents reported shopping at the nearest supermarket. The risk of obesity was not associated with street network distances between home and the nearest supermarket or the supermarket that SOS participants reported as their primary food source. The type of supermarket, by price, was found to be inversely and significantly associated with obesity rates, even after adjusting for individual-level sociodemographic and lifestyle variables, and proximity measures (adjusted relative risk = 0.34; 95% confidence interval = 0.19, 0.63) Conclusions. Improving physical access to supermarkets may be one strategy to deal with the obesity epidemic; improving economic access to healthy foods is another. [ABSTRACT FROM AUTHOR]; Copyright of American Journal of Public Health is the property of American Public Health Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Keywords

Natural Foods; Obesity Risk Factors; Surveys; Cluster Analysis (statistics); Confidence Intervals; Correlation (statistics); Food Service; Geographic Information Systems; Poisson Distribution; Population Geography; Research Funding; User Charges; Residential Patterns; Socioeconomic Factors; Relative Medical Risk; Statistical Models; Descriptive Statistics; Economics; Washington (state)

Valuing the Reliability of the Electrical Power Infrastructure: A Two-Stage Hedonic Approach

Maliszewski, Paul; Larson, Elisabeth; Perrings, Charles. (2013). Valuing the Reliability of the Electrical Power Infrastructure: A Two-Stage Hedonic Approach. Urban Studies, 50(1), 72 – 87.

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Abstract

The reliability of electrical power supply is amongst the conditions that inform house purchase decisions in all urban areas. Reliability depends in part on the conditions of the power generation and distribution infrastructures involved, and in part on environmental conditions. Its value to homeowners may be capitalised into the value of the house. In this paper, a hedonic pricing approach is used to estimate the capitalised value of the reliability offered by distribution infrastructures and the environmental conditions with which they interact in Phoenix, Arizona. A first stage estimates the impact of infrastructure and environmental conditions on reliability. In a second stage, the capitalised value of reliability from the marginal willingness to pay for reliability revealed by house purchase decisions is estimated and used to infer the value of both infrastructural characteristics and environmental conditions.

Keywords

Willingness-to-pay; Residential Property-values; Economic Valuation; Choice Experiment; Urban Wetlands; Air-quality; Benefits; Identifiability; Specification; Determinants