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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

Comparative Analysis of Hospital Energy Use: Pacific Northwest and Scandinavia

Burpee, Heather; McDade, Erin. (2014). Comparative Analysis of Hospital Energy Use: Pacific Northwest and Scandinavia. Health Environments Research & Design Journal (HERD) (Vendome Group LLC), 8(1), 20 – 44.

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Abstract

OBJECTIVE: This study aimed to establish the potential for significant energy reduction in hospitals in the United States by providing evidence of Scandinavian operational precedents with high Interior Environmental Quality (IEQ) and substantially lower energy profiles than comparable U.S. facilities. These facilities set important precedents for design teams seeking operational examples for achieving aggressive energy and interior environmental quality goals. This examination of operational hospitals is intended to offer hospital owners, designers, and building managers a strong case and concrete framework for strategies to achieve exceptionally high performing buildings. BACKGROUND: Energy efficient hospitals have the potential to significantly impact the U.S.'s overall energy profile, and key stakeholders in the hospital industry need specific, operationally grounded precedents in order to successfully implement informed energy reduction strategies. This study is an outgrowth of previous research evaluating high quality, low energy hospitals that serve as examples for new high performance hospital design, construction, and operation. Through extensive interviews, numerous site visits, the development of case studies, and data collection, this team has established thorough qualitative and quantitative analyses of several contemporary hospitals in Scandinavia and the Pacific Northwest. Many Scandinavian hospitals demonstrate a low energy profile, and when analyzed in comparison with U.S. hospitals, such Scandinavian precedents help define the framework required to make significant changes in the U.S. hospital building industry. METHODS: Eight hospitals, four Scandinavian and four Pacific Northwest, were quantitatively compared using the Environmental Protection Agency's Portfolio Manager, allowing researchers to answer specific questions about the impact of energy source and architectural and mechanical strategies on energy efficiency in operational hospitals. RESULTS: Specific architectural, mechanical, and plant systems make these Scandinavian hospitals more energy efficient than their Pacific Northwest counterparts. More importantly, synergistic systems integration allows for their significant reductions in energy consumption. CONCLUSIONS: This quantitative comparison of operational Scandinavian and Pacific Northwest hospitals resulted in compelling evidence of the potential for deep energy savings in the U.S., and allowed researchers to outline specific strategies for achieving such reductions.

Keywords

Environmental Quality; Energy Consumption; Health Facility Design & Construction; Comparative Studies; Energy Consumption In Hospitals; Pacific Northwest; Scandinavia; Built Environment; Case Study; Design Process; Healthcare Facility Design; Hospital; Post Occupancy

How Do Built-Environment Factors Affect Travel Behavior? A Spatial Analysis at Different Geographic Scales

Hong, Jinhyun; Shen, Qing; Zhang, Lei. (2014). How Do Built-Environment Factors Affect Travel Behavior? A Spatial Analysis at Different Geographic Scales. Transportation, 41(3), 419 – 440.

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Abstract

Much of the literature shows that a compact city with well-mixed land use tends to produce lower vehicle miles traveled (VMT), and consequently lower energy consumption and less emissions. However, a significant portion of the literature indicates that the built environment only generates some minor-if any-influence on travel behavior. Through the literature review, we identify four major methodological problems that may have resulted in these conflicting conclusions: self-selection, spatial autocorrelation, inter-trip dependency, and geographic scale. Various approaches have been developed to resolve each of these issues separately, but few efforts have been made to reexamine the built environment-travel behavior relationship by considering these methodological issues simultaneously. The objective of this paper is twofold: (1) to better understand the existing methodological gaps, and (2) to reexamine the effects of built-environment factors on transportation by employing a framework that incorporates recently developed methodological approaches. Using the Seattle metropolitan region as our study area, the 2006 Household Activity Survey and the 2005 parcel and building data are used in our analysis. The research employs Bayesian hierarchical models with built-environment factors measured at different geographic scales. Spatial random effects based on a conditional autoregressive specification are incorporated in the hierarchical model framework to account for spatial contiguity among Traffic Analysis Zones. Our findings indicate that land use factors have highly significant effects on VMT even after controlling for travel attitude and spatial autocorrelation. In addition, our analyses suggest that some of these effects may translate into different empirical results depending on geographic scales and tour types.

Keywords

Land-use; Urban Form; Multilevel Models; Physical-activity; Neighborhood; Choice; Impact; Specification; Accessibility; Causation; Built Environment; Travel Behavior; Self-selection; Spatial Autocorrelation; Bayesian Hierarchical Model

Multistate Evaluation of Safe Routes to School Programs

Stewart, Orion; Moudon, Anne Vernez; Claybrooke, Charlotte. (2014). Multistate Evaluation of Safe Routes to School Programs. American Journal Of Health Promotion, 28, S89 – S96.

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Abstract

Purpose. State Safe Routes to School (SRTS) programs provide competitive grants to local projects that support safe walking, bicycling, and other modes of active school travel (AST). This study assessed changes in rates of AST after implementation of SRTS projects at multiple sites across four states. Design. One-group pretest and posttest. Setting. Florida, Mississippi, Washington, and Wisconsin. Subjects. Convenience sample of 48 completed SRTS projects and 53 schools affected by a completed SRTS project. Intervention. State-funded SRTS project. Measures. AST was measured as the percentage of students walking, bicycling, or using any AST mode. SRTS project characteristics were measured at the project, school, and school neighborhood levels. Analysis. Paired-samples t-tests were used to assess changes in AST. Bivariate analysis was used to identify SRTS project characteristics associated with increases in AST. Data were analyzed separately at the project (n = 48) and school (n = 53) levels. Results. Statistically significant increases in AST were observed across projects in all four states. All AST modes increased from 12.9% to 17.6%; walking from 9.8% to 14.2%; and bicycling from 2.5% to 3.0%. Increases in rates of bicycling were negatively correlated with baseline rates of bicycling. Conclusion. State-funded SRTS projects are achieving one of the primary program goals of increasing rates of AST. They may be particularly effective at introducing bicycling to communities where it is rare. The evaluation framework introduced in this study can be used to continue tracking the effect of state SRTS programs as more projects are completed.

Keywords

Transportation Of School Children; Physical Activity Measurement; Health Promotion; Cycling; Walking; School Children -- United States; Bicycling; Children; Commuting; Health Focus: Fitness/physical Activity; Manuscript Format: Research; Outcome Measure: Behavioral; Prevention Research; Research Purpose: Program Evaluation; Schools; Setting: School; Strategy: Skill Building/behavior Change, Built Environment; Study Design: Quasi-experimental; Target Population Age: Youth; Target Population Circumstances: Geographic Location; Physical-activity; Mental-health; Travel; Association; Validity; Mode; Bus

The Spatial Clustering of Obesity: Does the Built Environment Matter?

Huang, R.; Moudon, A. V.; Cook, A. J.; Drewnowski, A. (2015). The Spatial Clustering of Obesity: Does the Built Environment Matter? Journal Of Human Nutrition & Dietetics, 28(6), 604 – 612.

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Abstract

BackgroundObesity rates in the USA show distinct geographical patterns. The present study used spatial cluster detection methods and individual-level data to locate obesity clusters and to analyse them in relation to the neighbourhood built environment. MethodsThe 2008-2009 Seattle Obesity Study provided data on the self-reported height, weight, and sociodemographic characteristics of 1602 King County adults. Home addresses were geocoded. Clusters of high or low body mass index were identified using Anselin's Local Moran's I and a spatial scan statistic with regression models that searched for unmeasured neighbourhood-level factors from residuals, adjusting for measured individual-level covariates. Spatially continuous values of objectively measured features of the local neighbourhood built environment (SmartMaps) were constructed for seven variables obtained from tax rolls and commercial databases. ResultsBoth the Local Moran's I and a spatial scan statistic identified similar spatial concentrations of obesity. High and low obesity clusters were attenuated after adjusting for age, gender, race, education and income, and they disappeared once neighbourhood residential property values and residential density were included in the model. ConclusionsUsing individual-level data to detect obesity clusters with two cluster detection methods, the present study showed that the spatial concentration of obesity was wholly explained by neighbourhood composition and socioeconomic characteristics. These characteristics may serve to more precisely locate obesity prevention and intervention programmes.

Keywords

Real Property; Ecology; Age Distribution; Anthropometry; Black People; Cluster Analysis (statistics); Communities; Computer Software; Epidemiological Research; Geographic Information Systems; Hispanic Americans; Mathematics; Obesity; Population Geography; Probability Theory; Race; Regression Analysis; Research Funding; Restaurants; Statistical Sampling; Self-evaluation; Sex Distribution; Shopping; Surveys; Telephones; Transportation; White People; Socioeconomic Factors; Body Mass Index; Data Analysis Software; Medical Coding; Statistical Models; Descriptive Statistics; Odds Ratio; Economics; Washington (state); Built Environment; Local Moran's I; Spatial Scan Statistic; Body-mass Index; Physical-activity; United-states; Risk-factors; Neighborhood; Association; Density; Disease; Disparities; Prevalence

Periurbanization and the Politics of Development-as-City-Building in China

Abramson, Daniel Benjamin. (2016). Periurbanization and the Politics of Development-as-City-Building in China. Cities, 53, 156 – 162.

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Abstract

China stands out among recently urbanized societies for the planned physicality of its rural-urban transformation the extensive marshaling of labor, capital and material resources to remake its cities and to transform rural land and communities into new, formal urban space. In China, the rural and the urban are distinguished in deeply dichotomous institutions of government, and peri-urbanization, defined as the disorderly spaces, processes and conditions of becoming urban, would appear to be a temporary stage of transition between an old rural socio-spatial order to a new urban socio-spatial order. The actual contested politics of development as-urbanization suggests otherwise, however, both on a national scale and on a community scale. The definition of development itself is at stake, and emerges unpredictably from peri-urban experience. A view of periurbanization as a process of socio-ecological adaptation is better suited to societies that have evolved in long settled, densely populated anthropogenic agrarian landscapes. (C) 2015 Published by Elsevier Ltd.

Keywords

Urban-growth; Chengdu; Urbanization; Adaptation; Resilience; Alternative Development; Socialist New Countryside Construction; New Rural Reconstruction

Innovative Linear Formulation for Transportation Reconstruction Planning

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

Advancing Urban Ecology toward a Science of Cities

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

Comparing Associations between the Built Environment and Walking in Rural Small Towns and a Large Metropolitan Area

Stewart, Orion T.; Moudon, Anne Vernez; Saelens, Brian E.; Lee, Chanam; Kang, Bumjoon; Doescher, Mark P. (2016). Comparing Associations between the Built Environment and Walking in Rural Small Towns and a Large Metropolitan Area. Environment And Behavior, 48(1), 13 – 36.

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Abstract

The association between the built environment (BE) and walking has been studied extensively in urban areas, yet little is known whether the same associations hold for smaller, rural towns. This analysis examined objective measures of the BE around participants' residence and their utilitarian and recreational walking from two studies, one in the urban Seattle area (n = 464) and the other in nine small U.S. towns (n = 299). After adjusting for sociodemographics, small town residents walked less for utilitarian purposes but more for recreational purposes. These differences were largely explained by differential associations of the BE on walking in the two settings. In Seattle, the number of neighborhood restaurants was positively associated with utilitarian walking, but in small towns, the association was negative. In small towns, perception of slow traffic on nearby streets was positively associated with recreational walking, but not in Seattle. These observations suggest that urban-rural context matters when planning BE interventions to support walking.

Keywords

Physical-activity; Utilitarian Walking; Transportation; Obesity; Adults; Travel; Urban; Prevalence; Strategies; Physical Activity; Walkability; City Planning; Urban Design; Community Health; Gis (geographic Information System); Gps (global Positioning System); Accelerometer; Effect Modification

Warning Triggers in Environmental Hazards: Who Should Be Warned to Do What and When?

Cova, Thomas J.; Dennison, Philip E.; Li, Dapeng; Drews, Frank A.; Siebeneck, Laura K.; Lindell, Michael K. (2017). Warning Triggers in Environmental Hazards: Who Should Be Warned to Do What and When? Risk Analysis, 37(4), 601 – 611.

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Abstract

Determining the most effective public warnings to issue during a hazardous environmental event is a complex problem. Three primary questions need to be answered: Who should take protective action? What is the best action? and When should this action be initiated? Warning triggers provide a proactive means for emergency managers to simultaneously answer these questions by recommending that a target group take a specified protective action if a preset environmental trigger condition occurs (e.g., warn a community to evacuate if a wildfire crosses a proximal ridgeline). Triggers are used to warn the public across a wide variety of environmental hazards, and an improved understanding of their nature and role promises to: (1) advance protective action theory by unifying the natural, built, and social themes in hazards research into one framework, (2) reveal important information about emergency managers' risk perception, situational awareness, and threat assessment regarding threat behavior and public response, and (3) advance spatiotemporal models for representing the geography and timing of disaster warning and response (i.e., a coupled natural-built-social system). We provide an overview and research agenda designed to advance our understanding and modeling of warning triggers.

Keywords

Situation Awareness; Evacuation; Model; Management; Simulation; Decisions; Vehicles; Support; Systems; Hazards; Protective Actions; Warning Systems; Emergency Communications Systems; Disasters; Emergency Preparedness; Environmental Hazards; Environmental Conditions; Public Concern; Risk Perception; Emergency Management; Situational Awareness; Information Management; Geography; Emergency Warning Programs; Wildfires; Action; Risk Assessment; Timing; Warnings