Stewart, Orion T.; Moudon, Anne Vernez; Littman, Alyson J.; Seto, Edmund; Saelens, Brian E. (2018). The Association between Park Facilities and Duration of Physical Activity During Active Park Visits. Journal Of Urban Health, 95(6), 869 – 880.
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Abstract
Public parks provide places for urban residents to obtain physical activity (PA), which is associated with numerous health benefits. Adding facilities to existing parks could be a cost-effective approach to increase the duration of PA that occurs during park visits. Using objectively measured PA and comprehensively measured park visit data among an urban community-dwelling sample of adults, we tested the association between the variety of park facilities that directly support PA and the duration of PA during park visits where any PA occurred. Cross-classified multilevel models were used to account for the clustering of park visits (n=1553) within individuals (n=372) and parks (n=233). Each additional different PA facility at a park was independently associated with a 6.8% longer duration of PA bouts that included light-intensity activity, and an 8.7% longer duration of moderate to vigorous PA time. Findings from this study are consistent with the hypothesis that more PA facilities increase the amount of PA that visitors obtain while already active at a park.
Keywords
Park Facilities; Physical Activity; Park Use; Recreation; Built Environment; Global Positioning System; Accelerometer; Gis; Gps; Accelerometer Data; United-states; Adults; Proximity; Features; Walking; Size; Attractiveness; Improvements; Environment; Parks & Recreation Areas; Parks; Luminous Intensity; Clustering; Urban Areas
Bender, W.; Waytuck, D.; Wang, S.; Reed, D. A. (2018). In Situ Measurement of Wind Pressure Loadings on Pedestal Style Rooftop Photovoltaic Panels. Engineering Structures, 163, 281 – 293.
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Abstract
The installation of rooftop photovoltaic (PV) arrays is increasing throughout the US. Until recently, pedestal type PV framing systems for rooftops were basically designed using procedures from the ASCE7-10 Components and Cladding Standard for rooftop equipment. The 2011 Japanese Standard Load design guide on structures for photovoltaic arrays was useful in characterizing the pressure coefficients on rooftops, but the Standard employs different wind speed and importance factors, making its use in the US quite limited, Even the updated 2017 version is written for a different audience. Because rooftop pressure loadings are high due to flow separation, SEAOC and other organizations contracted boundary layer wind tunnel tests of panels attached to rooftops to ascertain if the ASCE7-10 equipment loadings were appropriate. The investigations resulted in new standards for pedestal-style arrays that appear in Chapter 29 of ASCE7-16. However, the new standards are limited to simple geometries and orientations, and the dynamics of the simply-supported thin PV plates do not appear to be considered. Questions regarding the ability of the boundary tunnels to simulate accurately the turbulence at the scale required for the attached panels have been raised. In response, very limited full-scale investigations in large-scale tunnels and in situ have been undertaken to calibrate the tunnel results. The results of this paper represent one of these calibration investigations. Specifically, in situ full-scale net wind pressure loadings on a rooftop PV array in a pedestal-style framing system located on the three story Hogue Technology Building of Central Washington University (CWU) in Ellensburg, Washington were measured. The CWU campus has a rural setting in a region with steady winds: Ellensburg is located in the Kittitas Breezeway portion of the Northwest wind power region. Indeed, the Wild Horse Wind and Solar Farm is located on the outskirts of town. The data described here were collected from April through August 2014. The measured net pressure coefficient time series were similar to those for rooftop pressure loadings for low-rise buildings described in the literature such as the Wind Engineering Research Field Laboratory at Texas Tech University (Ham and Bienkiewicz, 1998 [1]; Levitan and Mehta, 1992 [2]). The analysis of the net pressure time series data included an examination of the minimum, maximum, mean, and RMS values. Preliminary results suggest that the range of the values is larger than assumed in the ASCE7 Standard, and that the magnitude of the loadings vary considerably spatially over the multiple panel array. The pressure loading measurements are ongoing.
Keywords
Building Integrated Photovoltaics; Buildings (structures); Calibration; Design Engineering; Pressure Measurement; Roofs; Solar Cell Arrays; Standards; Time Series; Turbulence; Wind Tunnels; Japanese Standard Load Design Guide; Wind Pressure Loading Measurements; Asce7-10 Components-cladding Standard; Tunnel Calibration; Texas Tech University; Kittitas Breezeway Portion; Wild Horse Wind And Solar Farm; Ellensburg; Central Washington University; Hogue Technology Building; Boundary Layer Wind Tunnel Test; Flow Separation; Multiple Panel Array; Wind Engineering Research Field Laboratory; Net Pressure Coefficient Time Series; Northwest Wind Power Region; Pedestal-style Framing System; Pv Plates; Rooftop Equipment; Pedestal Style Rooftop Photovoltaic Panels; Solar-arrays; Loads; Simulation; Wind Engineering; Photovoltaic Modules; Solar Energy; Full-scale Measurements; Wind Loadings; Photovoltaic Cells; Roofing; Wind Power; Structural Engineering; Boundary Layers; Cladding; Wind Tunnel Testing; Solar Cells; In Situ Measurement; Framing; Photovoltaics; Engineering Research; Wind Measurement; Pressure; Panels; Wind Pressure; Design Standards; Fluid Dynamics; Low Rise Buildings; Colleges & Universities; Wind Speed; United States--us
Korn, Abigail; Bolton, Susan M.; Spencer, Benjamin; Alarcon, Jorge A.; Andrews, Leann; Voss, Joachim G. (2018). Physical and Mental Health Impacts of Household Gardens in an Urban Slum in Lima, Peru. International Journal Of Environmental Research And Public Health, 15(8).
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Abstract
Rural poverty and lack of access to education has led to urban migration and fed the constant growth of urban slums in Lima, Peru. Inhabitants of these informal settlements lack land rights and access to a public water supply, resulting in poor sanitation, an inability to grow food, and suboptimal health outcomes. A repeated measures longitudinal pilot study utilizing participatory design methods was conducted in Lima between September 2013 and September 2014 to determine the feasibility of implementing household gardens and the subsequent impact of increased green space on well-being. Anthropometric data and a composite of five validated mental health surveys were collected at the baseline, 6-months, and 12-months after garden construction. Significant increases from the baseline in all domains of quality of life, including: physical (p < 0.01), psychological (p = 0.05), social (p = 0.02), environmental (p = 0.02), and overall social capital (p < 0.01) were identified 12 months after garden construction. Life-threatening experiences decreased significantly compared to the baseline (p = 0.02). There were no significant changes in parent or partner empathy (p = 0.21), BMI (p = 0.95), waist circumference (p = 0.18), or blood pressure (p = 0.66) at 6 or 12 months. Improved access to green space in the form of a household garden can significantly improve mental health in an urban slum setting.
Keywords
Of-life Assessment; Psychometric Properties; Threatening Experiences; Vegetable Consumption; Developing-countries; Community Garden; Climate-change; Green Space; Poverty; Participation; Mental Health; Peru; Quality Of Life; Urban Slum; Social Capital
Stewart, Orion T.; Moudon, Anne Vernez; Littman, Alyson J.; Seto, Edmund; Saelens, Brian E. (2018). Why Neighborhood Park Proximity Is Not Associated with Total Physical Activity. Health & Place, 52, 163 – 169.
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Abstract
This study explored how parks within the home neighborhood contribute to total physical activity (PA) by isolating park-related PA. Seattle-area adults (n = 634) were observed using time-matched accelerometer, Global Positioning System (GPS), and travel diary instruments. Of the average 42.3 min of daily total PA, only 11% was related to parks. Both home neighborhood park count and area were associated with park-based PA, but not with PA that occurred elsewhere, which comprised 89% of total PA. This study demonstrates clear benefits of neighborhood parks for contributing to park-based PA while helping explain why proximity to parks is rarely associated with overall PA.
Keywords
Physical Activity; Parks; Urban Planning; Environmental Health; Global Positioning System; Built Environment; Green Space; Recreation; Social Determinants Of Health; Health Research; Accelerometer Data; Self-selection; United-states; Public Parks; Older Women; Walking; Adults; Facilities
Chen, Peng; Liu, Qian; Sun, Feiyang. (2018). Bicycle Parking Security and Built Environments. Transportation Research: Part D, 62, 169 – 178.
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Abstract
The lack of secure bicycle parking is a serious but often neglected issue that discourages bicycling. Classical environment criminology theories try to explain the pattern of bicycle theft but provide limited insights into the relationship between crime and the built environment. This study examines the association between built environment factors and bicycle theft using a zero inflated negative binomial model to account for data over-dispersion and excess zeros. The assembled dataset provides variables pertaining to the road network, land use, bicycle travel demand, and socio-demographics. The key findings are as follows: (1) Bicycle theft is more likely to occur in areas for commercial purposes, areas with a high population or employment density, and areas with more bike lanes or sidewalks. (2) Bicycle theft is likely to occur at sites with more bike racks or bus stops. (3) Bicycle theft is more likely to occur at mid-blocks than at intersections. (4) Bicycle theft is more likely to occur in neighborhoods with a greater percentage of socially disadvantaged people and in neighborhoods where residents' median age is lower. (5) The likelihood of losing a bicycle is lower in areas with more bicycle trips. In general, the number of bicycle thefts increases in dense areas with more targets and decreases with greater natural guardianship provided by more passersby. With respect to policy implications, governments and transport planners should implement a geographically-differentiated surveillance strategy, encourage bicycling, improve the visibility of bike racks to the public, and promote surveillance and natural guardianship in densely developed areas.
Keywords
Bicycle Parking; Cycling; Bicycle Theft; Sociodemographic Factors; Bicycles; Environmental Aspects; Built Environment; Environment Criminology; Urban Design; Zero-inflated Negative Binomial Model; Crime; Theft; Risk; Opportunities; Behavior; Travel
Lacoe, Johanna; Bostic, Raphael W.; Acolin, Arthur. (2018). Crime and Private Investment in Urban Neighborhoods. Journal Of Urban Economics, 108, 154 – 169.
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Abstract
The question of how best to improve neighborhoods that lag behind has drawn considerable attention from policy-makers, practitioners, and academics, yet there remains a vigorous debate regarding the best approaches to accomplish community development. This paper investigates the role crime policy plays in shaping the trajectory of neighborhoods. Much of the existing research on neighborhood crime was conducted in rising-crime environments, and the evidence was clear: high levels of crime have adverse effects on neighborhoods and resident quality of life, This study examines how private investment in neighborhoods in two cities Chicago and Los Angeles changed as the incidence of neighborhood crime changed during the 2000s, a period when crime was declining city-wide in both places. Using detailed blockface-level data on the location of crime and private investments between 2006 and 2011, the analysis answers the question: Do changes in crime affect private development decisions? The results show that private investment, as represented by building permits, decreases on blocks where crime increases in the past year. We also find that the relationship between crime and private investment is not symmetric private investment appears to only be sensitive to crime in rising crime contexts. The result is present in both cities, and robust to multiple definitions of crime and the elimination of outliers and the main commercial district. These results suggest that crime-reduction policies can be an effective economic development tool, but only in certain neighborhoods facing specific circumstances.
Keywords
Enterprise Zones; Crime; Investment; Neighborhoods
Stewart, Orion Theodore; Moudon, Anne Vernez; Littman, Alyson; Seto, Edmund; Saelens, Brian E. (2018). The Association between Park Facilities and the Occurrence of Physical Activity during Park Visits. Journal Of Leisure Research, 49(3-5), 217 – 235.
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Abstract
Prior research has found a positive relationship between the variety of park facilities and park-based physical activity (PA) but has not provided an estimate of the effect that additional different PA facilities have on whether an individual is active during a park visit. Using objective measures of park visits and PA from an urban sample of 225 adults in King County, Washington, we compared the variety of PA facilities in parks visited where an individual was active to PA facilities in parks where the same individual was sedentary. Each additional different PA facility at a park was associated with a 6% increased probability of being active during a visit. Adding different PA facilities to a park appears to have a moderate effect on whether an individual is active during a park visit, which could translate into large community health impacts when scaled up to multiple park visitors.
Keywords
Accelerometer Data; Built Environment; Walking; Density; Health; Adults; Size; Gps; Attractiveness; Improvements; Measurement; Parks; Physical Activity; Quantitative Research; Urban Planning
Chen, Peng; Shen, Qing; Childress, Suzanne. (2018). A GPS Data-based Analysis of Built Environment Influences on Bicyclist Route Preferences. International Journal Of Sustainable Transportation, 12(3), 218 – 231.
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Abstract
This study examines the effects of built environment features, including factors of land use and road network, on bicyclists' route preferences using the data from the city of Seattle. The bicycle routes are identified using a GPS dataset collected from a smartphone application named CycleTracks. The route choice set is generated using the labeling route approach, and the cost functions of route alternatives are based on principal component analyses. Then, two mixed logit models, focusing on random parameters and alternative-specific coefficients, respectively, are estimated to examine bicyclists' route choice. The major findings of this study are as follows: (1) the bicycle route choice involves the joint consideration of convenience, safety, and leisure; (2) most bicyclists prefer to cycle on shorter, flat, and well-planned bicycle facilities with slow road traffic; (3) some bicyclists prefer routes surrounded by mixed land use; (4) some bicyclists favor routes which are planted with street trees or installed with street lights; and (5) some bicyclists prefer routes along with city features. This analysis provides valuable insights into how well-planned land use and road network can facilitate efficient, safe, and enjoyable bicycling.
Keywords
Cyclists; Mobile Apps; Multiple Correspondence Analysis (statistics); Traffic Engineering; Cycling; Bicycle Route Choice; Built Environment; Labeling Routes; Mixed Logit Model; Principal Component Analysis; Smartphone GPS Data; Choice Sets; Safe Routes; Walking; Models; Health; Infrastructure; Facilities; California; Networks
Lee, Hyun Woo; Harapanahalli, Bharat Anand; Nnaji, Chukwuma; Kim, Jonghyeob; Gambatese, John. (2018). Feasibility of Using QR Codes in Highway Construction Document Management. Transportation Research Record, 2672(26), 114 – 123.
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Abstract
Highway construction occasionally takes place in remote locations, making its document management challenging especially when frequent document revisions occur. With the recent advancement of smartphones and tablets, Quick Response (QR) codes can provide project teams rapid and reliable access to up-to-date documents required for field operations. As a result, the use of QR codes can lead to a reduced need for traveling or meeting for document revisions, and reduce the amount of hardcopy documents and storage space. Despite the potential for significant benefits, there have been few studies aimed at assessing the feasibility of using QR codes in highway construction. In response, the objective of the study was to investigate the benefits of and barriers to using QR codes in highway construction for document management. To conduct the study, first a multi-step process was used, involving an online survey and interviews, with a goal of determining the status quo of highway construction in terms of document management and mobile information technology (IT). The results indicate that hardcopy documentation is still the most prevalent form of document management in highway construction, and hence there is an opportunity for implementing QR codes in conjunction with mobile IT. In the second part of the study, a time study using a real-world infrastructure project was conducted based on three activities: detail look up, specification check, and version check. As a result, the study found statistical evidence that using QR codes can lead to significant time savings.
Keywords
Highway Planning; Information Services; Road Construction; Document Management; Field Operation; Highway Construction; Infrastructure Project; Online Surveys; Quick Response Code; Remote Location; Statistical Evidence
Sun, Feiyang; Chen, Peng; Jiao, Junfeng. (2018). Promoting Public Bike-Sharing: A Lesson from the Unsuccessful Pronto System. Transportation Research: Part D, 63, 533 – 547.
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Abstract
In 2014, Seattle implemented its own bike-sharing system, Pronto. However, the system ultimately ceased operation three years later on March 17th, 2017. To learn from this failure, this paper seeks to understand factors that encourage, or discourage, bike-sharing trip generation and attraction at the station level. This paper investigates the effects of land use, roadway design, elevation, bus trips, weather, and temporal factors on three-hour long bike pickups and returns at each docking station. To address temporal autocorrelations and the nonlinear seasonality, the paper implements a generalized additive mixed model (GAMM) that incorporates the joint effects of a time metric and time-varying variables. The paper estimates models on total counts of pickups and returns, as well as pickups categorized by user types and by location. The results clarify that effects of hilly terrain and the rainy weather, two commonly perceived contributors to the failure. Additionally, results suggest that users in the University District, presumably mostly university students, tend to use shared bikes in neighborhoods with a higher household density and a higher percentage of residential land use, and make bike-sharing trips regardless workdays or non-workdays. The paper also contributes to the discussion on the relationship between public transportation service and bike-sharing. In general, users tend to use bike-sharing more at stations that have more scheduled bus trips nearby. However, some bike-sharing users may shift to bus services during peak hours and rainy weather. Several strategies are proposed accordingly to increase bike ridership in the future.
Keywords
Bicycle Sharing Programs; Urban Transportation; Transportation & The Environment; Land Use Planning; Time-varying Systems; Bike-sharing; Built Environment; Generalized Additive Mixed Model; Pronto; Temporal Factors; Built Environment Factors; Bicycle; Impact; Transportation; Walking; Usage