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Walking Objectively Measured: Classifying Accelerometer Data with GPS and Travel Diaries

Kang, Bumjoon; Moudon, Anne V.; Hurvitz, Philip M.; Reichley, Lucas; Saelens, Brian E. (2013). Walking Objectively Measured: Classifying Accelerometer Data with GPS and Travel Diaries. Medicine & Science In Sports & Exercise, 45(7), 1419 – 1428.

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Abstract

Purpose: This study developed and tested an algorithm to classify accelerometer data as walking or nonwalking using either GPS or travel diary data within a large sample of adults under free-living conditions. Methods: Participants wore an accelerometer and a GPS unit and concurrently completed a travel diary for seven consecutive days. Physical activity (PA) bouts were identified using accelerometry count sequences. PA bouts were then classified as walking or nonwalking based on a decision-tree algorithm consisting of seven classification scenarios. Algorithm reliability was examined relative to two independent analysts' classification of a 100-bout verification sample. The algorithm was then applied to the entire set of PA bouts. Results: The 706 participants' (mean age = 51 yr, 62% female, 80% non-Hispanic white, 70% college graduate or higher) yielded 4702 person-days of data and had a total of 13,971 PA bouts. The algorithm showed a mean agreement of 95% with the independent analysts. It classified PA into 8170 walking bouts (58.5 %) and 5337 nonwalking bouts (38.2%); 464 bouts (3.3%) were not classified for lack of GPS and diary data. Nearly 70% of the walking bouts and 68% of the nonwalking bouts were classified using only the objective accelerometer and GPS data. Travel diary data helped classify 30% of all bouts with no GPS data. The mean + SD duration of PA bouts classified as walking was 15.2 + 12.9 min. On average, participants had 1.7 walking bouts and 25.4 total walking minutes per day. Conclusions: GPS and travel diary information can be helpful in classifying most accelerometer-derived PA bouts into walking or nonwalking behavior.

Keywords

Walking; Algorithms; Decision Trees; Geographic Information Systems; Research Funding; Travel; Accelerometry; Diary (literary Form); Descriptive Statistics; Algorithm; Classification; Physical Activity; Walk Trip; Global Positioning Systems; Physical-activity; Environment; Behaviors; Validity; Location

The Influence of Street Environments on Fuel Efficiency: Insights from Naturalistic Driving

Wang, X.; Liu, C.; Kostyniuk, L.; Shen, Q.; Bao, S. (2014). The Influence of Street Environments on Fuel Efficiency: Insights from Naturalistic Driving. International Journal Of Environmental Science And Technology, 11(8), 2291 – 2306.

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Abstract

Fuel consumption and greenhouse gas emissions in the transportation sector are a result of a three-legged stool: fuel types, vehicle fuel efficiency, and vehicle miles travelled (VMT). While there is a substantial body of literature that examines the connection between the built environment and total VMT, few studies have focused on the impacts of the street environment on fuel consumption rate. Our research applied structural equation modeling to examine how driving behaviors and fuel efficiency respond to different street environments. We used a rich naturalistic driving dataset that recorded detailed driving patterns of 108 drivers randomly selected from the Southeast Michigan region. The results show that, some features of compact streets such as lower speed limit, higher intersection density, and higher employment density are associated with lower driving speed, more speed changes, and lower fuel efficiency; however, other features such as higher population density and higher density of pedestrian-scale retails improve fuel efficiency. The aim of our study is to gain further understanding of energy and environmental outcomes of the urban areas and the roadway infrastructure we plan, design, and build and to better inform policy decisions concerned with sustainable transportation.

Keywords

Travel; Consumption; Emissions; Cities; Energy; Street Environments; Fuel Efficiency; Structural Equation Modeling; Naturalistic Driving

Rediscovering Japanese Urban Space in a World Context

Oshima, Ken Tadashi. (2016). Rediscovering Japanese Urban Space in a World Context. Journal Of Urban History, 42(3), 623 – 633.

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Abstract

Counter to the rise of the modern metropolis in Japan in the era of high-speed growth following World War II, a movement to embrace elements of traditional townscapes that had been lost as rational urban planning took hold from the mid-1950s to the mid-1970s. During this period, the realities of large-scale urban development and increasing urban problems would eventually expose the limitations of functional planning and the need to preserve traditional structures and townscapes. While architects like Bruno Taut had praised the virtues of the farmhouse villages at Shirakawago in the 1930s and Yoshida Tetsur presented traditional Japanese architecture to an international audience as contemporary design before World War II, among others, the discourse subsequently shifted from Japanese objects and structures to urban space in the postwar period. This discourse on Japanese urban space would lead to the publication of Nihon no toshi kukan (Japanese Urban Space) in 1963 (1968 as a book) that presented the work of the Toshi dezain kenkyutai (Urban Design Research Group) including Isozaki Arata (1931-) and architectural historian It Teiji (1922-2010). This article analyzes the origins and implications of this work through a plethora of subsequent design surveys throughout Japan and other trajectories of research and design of Japanese urban space from the 1960s to the present.

Keywords

Japanese Urban Space; Urban Landscape; Serial Vision; Imageability; Design Survey

Planning in the Spirit of Deleuze and Guattari? Considering Community-Based Food Projects in the United States and Mexico

Purcell, Mark; Born, Branden. (2017). Planning in the Spirit of Deleuze and Guattari? Considering Community-Based Food Projects in the United States and Mexico. Urban Geography, 38(4), 521 – 536.

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Abstract

In this article we argue that planning theory and practice should engage more with the normative political vision of Gilles Deleuze and Felix Guattari. They reject the transcendent authority of the State and arguably by extension, planning. As planners we should be concerned: need we reconceptualize, or abandon the planning project? We outline their vision, highlighting key concepts including lines of flight, revolution, the new land, and immanent organization, and use two cases from the United States and Mexico, the Food Commons and Center for Integral Farmer Development in the Mixteca, to show that planning in accordance with Deleuze and Guattari may indeed be possible. We end with questions: is what we describe planning? And what is planning - or what should it be?

Keywords

Deleuze And Guattari; Planning Theory; Mexico; Food Systems

A Time-Based Objective Measure of Exposure to the Food Environment

Scully, Jason Y.; Moudon, Anne Vernez; Hurvitz, Philip M.; Aggarwal, Anju; Drewnowski, Adam. (2019). A Time-Based Objective Measure of Exposure to the Food Environment. International Journal Of Environmental Research And Public Health, 16(7).

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Abstract

Exposure to food environments has mainly been limited to counting food outlets near participants' homes. This study considers food environment exposures in time and space using global positioning systems (GPS) records and fast food restaurants (FFRs) as the environment of interest. Data came from 412 participants (median participant age of 45) in the Seattle Obesity Study II who completed a survey, wore GPS receivers, and filled out travel logs for seven days. FFR locations were obtained from Public Health Seattle King County and geocoded. Exposure was conceptualized as contact between stressors (FFRs) and receptors (participants' mobility records from GPS data) using four proximities: 21 m, 100 m, 500 m, and 1/2 mile. Measures included count of proximal FFRs, time duration in proximity to 1 FFR, and time duration in proximity to FFRs weighted by FFR counts. Self-reported exposures (FFR visits) were excluded from these measures. Logistic regressions tested associations between one or more reported FFR visits and the three exposure measures at the four proximities. Time spent in proximity to an FFR was associated with significantly higher odds of FFR visits at all proximities. Weighted duration also showed positive associations with FFR visits at 21-m and 100-m proximities. FFR counts were not associated with FFR visits. Duration of exposure helps measure the relationship between the food environment, mobility patterns, and health behaviors. The stronger associations between exposure and outcome found at closer proximities (<100 m) need further research.

Keywords

Global Positioning Systems; Physical-activity; Health Research; Land-use; Neighborhood; Gps; Obesity; Tracking; Validity; Mobility; Fast Food; Spatio-temporal Exposure; Mobility Patterns; Selective Mobility Bias

Measuring the Urban Forms of Shanghai’s City Center and Its New Districts: A Neighborhood-Level Comparative Analysis

Lin, Lin; Chen, Xueming (Jimmy); Moudon, Anne Vernez. (2021). Measuring the Urban Forms of Shanghai’s City Center and Its New Districts: A Neighborhood-Level Comparative Analysis. Sustainability, 13(15).

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Abstract

Rapid urban expansion has radically transformed the city centers and the new districts of Chinese cities. Both areas have undergone unique redevelopment and development over the past decades, generating unique urban forms worthy of study. To date, few studies have investigated development patterns and land use intensities at the neighborhood level. The present study aims to fill the gap and compare the densities of different types of developments and the spatial compositions of different commercial uses at the neighborhood level. We captured the attributes of their built environment that support instrumental activities of daily living of 710 neighborhoods centered on the public elementary schools of the entire Shanghai municipality using application programming interfaces provided in Baidu Map services. The 200 m neighborhood provided the best fit to capture the variations of the built environment. Overall, city center neighborhoods had significantly higher residential densities and housed more daily routine destinations than their counterparts in the new districts. Unexpectedly, however, the total length of streets was considerably smaller in city-center neighborhoods, likely reflecting the prominence of the wide multilane vehicular roads surrounding large center city redevelopment projects. The findings point to convergence between the city center's urban forms and that of the new districts.

Keywords

Quantifying Spatiotemporal Patterns; Fast-food Restaurants; Instrumental Activities; Physical-activity; Chinese Cities; Land; Schools; Redevelopment; Expansion; Transformation; Built Environment; Planning; Neighborhood; Urban Form; Shanghai

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

Characterizing the Food Environment: Pitfalls and Future Directions

Moudon, Anne Vernez; Drewnowski, Adam; Duncan, Glen E.; Hurvitz, Philip M.; Saelens, Brian E.; Scharnhorst, Eric. (2013). Characterizing the Food Environment: Pitfalls and Future Directions. Public Health Nutrition, 16(7), 1238 – 1243.

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Abstract

Objective: To assess a county population's exposure to different types of food sources reported to affect both diet quality and obesity rates. Design: Food permit records obtained from the local health department served to establish the full census of food stores and restaurants. Employing prior categorization schemes which classified the relative healthfulness of food sources based on establishment type (i.e. supermarkets v. convenience stores, or full-service v. fast-food restaurants), food establishments were assigned to the healthy, unhealthy or undetermined groups. Setting: King County, WA, USA. Subjects: Full census of food sources. Results: According to all categorization schemes, most food establishments in King County fell into the unhealthy and undetermined groups. Use of the food permit data showed that large stores, which included supermarkets as healthy food establishments, contained a sizeable number of bakery/delis, fish/meat, ethnic and standard quick-service restaurants and coffee shops, all food sources that, when housed in a separate venue or owned by a different business establishment, were classified as either unhealthy or of undetermined value to health. Conclusions: To fully assess the potential health effects of exposure to the extant food environment, future research would need to establish the health value of foods in many such common establishments as individually owned grocery stores and ethnic food stores and restaurants. Within-venue exposure to foods should also be investigated.

Keywords

Food Chemistry; Obesity; Health Boards; Dietary Supplements; Food Cooperatives; Restaurant Reviews; Coffee Shops; Food Consumption; Food Quality; Census Of Food Sources; Exposure; Health Value; Neighborhood Characteristics; Store Availability; Racial Composition; Physical-activity; Weight Status; Restaurants; Association; Proximity; Access; Business Enterprises; Fast Food Restaurants; Fish; Grocery Stores; Healthy Diet; Meat; Nutritional Adequacy; Supermarkets

Worksite Neighborhood and Obesogenic Behaviors: Findings among Employees in the Promoting Activity and Changes in Eating (PACE) Trial

Barrington, Wendy E.; Beresford, Shirley A. A.; Koepsell, Thomas D.; Duncan, Glen E.; Moudon, Anne Vernez. (2015). Worksite Neighborhood and Obesogenic Behaviors: Findings among Employees in the Promoting Activity and Changes in Eating (PACE) Trial. American Journal Of Preventive Medicine, 48(1), 31 – 41.

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Abstract

Background: Understanding mechanisms linking neighborhood context to health behaviors may provide targets for increasing lifestyle intervention effectiveness. Although associations between home neighborhood and obesogenic behaviors have been studied, less is known about the role of worksite neighborhood. Purpose: To evaluate associations between worksite neighborhood context at baseline (2006) and change in obesogenic behaviors of adult employees at follow-up (2007-2009) in a worksite randomized trial to prevent weight gain. Methods: Worksite property values were used as an indicator of worksite neighborhood SES (NSES). Worksite neighborhood built environment attributes associated with walkability were evaluated as explanatory factors in relationships among worksite NSES, diet, and physical activity behaviors of employees. Behavioral data were collected at baseline (2005-2007) and follow-up (2007-2009). Multilevel linear and logistic models were constructed adjusting for covariates and accounting for clustering within worksites. Product-of-coefficients methods were used to assess mediation. Analyses were performed after study completion (2011-2012). Results: Higher worksite NSES was associated with more walking (OR = 1.16, 95% CI = 1.03, 1.30, p = 0.01). Higher density of residential units surrounding worksites was associated with more walking and eating five or more daily servings of fruits and vegetables, independent of worksite NSES. Residential density partially explained relationships among worksite NSES, fruit and vegetable consumption, and walking. Conclusions: Worksite neighborhood context may influence employees' obesogenic behaviors. Furthermore, residential density around worksites could be an indicator of access to dietary and physical activity-related infrastructure in urban areas. This may be important given the popularity of worksites as venues for obesity prevention efforts. Published by Elsevier Inc. on behalf of American Journal of Preventive Medicine.

Keywords

Health Behavior; Food Habits; Lifestyles & Health; Prevention Of Obesity; Employee Health Promotion; Follow-up Studies (medicine); Local Food Environment; Dietary Energy Density; Body-mass Index; Socioeconomic-status; Physical-activity; Built Environment; Longitudinal-associations; Walking Behavior; Restaurant Use; Weight-gain

Study on the Ownership of Motorized and Non-Motorized Vehicles in Suburban Metro Station Areas: A Structural Equation Approach

Pan, Haixiao; Li, Jing; Chen, Peng. (2016). Study on the Ownership of Motorized and Non-Motorized Vehicles in Suburban Metro Station Areas: A Structural Equation Approach. Urban Rail Transit, 2(2), 47 – 58.

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Abstract

As Chinese megacities are experiencing a large-scale motorization and suburbanization, an ever greater number of households are relocated to suburban towns. The increasing average travel distance surely encourages car growth. China is now the world's largest car consumer, resulting in a series of unforeseen environmental and public health issues. On the other hand, scooters, electric bikes, and motorcycles become attractive options to substitute non-motorized bicycles. The ongoing demographic changes should also be taken in account. China has a rapidly aging population and a higher birth rate following reforms to the one-child policy allowing couples to have a second child. These changes will lead to a dramatic alteration of the household composition in the near future. Under above emerging contexts, this study aims to understand what implies the ownership of motorized and non-motorized vehicles in suburban metro station areas by means of a structural equation model. The data employed in this study are based on a household survey collected from three neighborhoods in Shanghai suburban metro station areas in 2010. The major findings include: (1) Income is a decisive element in car ownership. Specifically, high-income households have higher propensity to own a car, while middle and poor income families tend to own scooters, electric bikes, motorcycles, or bicycles. (2) Workplace built environment features or mode preferences are not essential to understanding vehicle ownership in Chinese context. (3) Stem families are more likely to own cars; the presence of a child or a senior family member increases the probability of owning a car by enlarging the household. (4) The results estimated for core family and DINK (couple with no child) family are highly consistent, and these families are less likely to own cars. Therefore, transport policies may focus more on households. Providing safe, pleasant, and efficient pedestrian and bicycle paths for children and seniors may decrease the attractiveness of owning cars.

Keywords

Suburban Metro Station Areas; Ownership Of Motorized And Non-motorized Vehicles; Built Environment; Mode Preferences; Family Composition; Structural Equation Model