Kang, Bumjoon; Scully, Jason Y.; Stewart, Orion; Hurvitz, Philip M.; Moudon, Anne V. (2015). Split-Match-Aggregate (SMA) Algorithm: Integrating Sidewalk Data with Transportation Network Data in GIS. International Journal Of Geographical Information Science, 29(3), 440 – 453.
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Abstract
Sidewalk geodata are essential to understand walking behavior. However, such geodata are scarce, only available at the local jurisdiction and not at the regional level. If they exist, the data are stored in geometric representational formats without network characteristics such as sidewalk connectivity and completeness. This article presents the Split-Match-Aggregate (SMA) algorithm, which automatically conflates sidewalk information from secondary geometric sidewalk data to existing street network data. The algorithm uses three parameters to determine geometric relationships between sidewalk and street segments: the distance between streets and sidewalk segments; the angle between sidewalk and street segments; and the difference between the lengths of matched sidewalk and street segments. The SMA algorithm was applied in urban King County, WA, to 13 jurisdictions' secondary sidewalk geodata. Parameter values were determined based on agreement rates between results obtained from 72 pre-specified parameter combinations and those of a trained geographic information systems (GIS) analyst using a randomly selected 5% of the 79,928 street segments as a parameter-development sample. The algorithm performed best when the distances between sidewalk and street segments were 12m or less, their angles were 25 degrees or less, and the tolerance was set to 18m, showing an excellent agreement rate of 96.5%. The SMA algorithm was applied to classify sidewalks in the entire study area and it successfully updated sidewalk coverage information on the existing regional-level street network data. The algorithm can be applied for conflating attributes between associated, but geometrically misaligned line data sets in GIS.
Keywords
Geodatabases; Sidewalks; Algorithms; Pedestrians; Digital Mapping; Algorithm; Gis; Pedestrian Network Data; Polyline Conflation; Sidewalk; Built Environment; Physical-activity; Mode Choice; Urban Form; Land-use; Travel; Generation; Walking
Lee, Wonil; Migliaccio, Giovanni Ciro. (2016). Physiological Cost Of Concrete Construction Activities. Construction Innovation, 16(3), 281 – 306.
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Abstract
Purpose - The purpose of this paper was to investigate the physiological cost of concrete construction activities. Design/methodology/approach - Five concrete construction workers were recruited. The workers' three-week heart rate (HR) data were collected in summer and autumn. In this paper, several HR indexes were used to investigate the physiological cost of work in concrete construction trades, including average working HR, relative HR and ratio of working HR to resting HR. Findings - This paper measures how absolute and relative HRs vary throughout a workday and how working HR compares to resting HR for individual workers. Research limitations/implications - Field observations are usually extremely difficult as researchers need to overcome a number of barriers, including employers' resistance to perceived additional liabilities, employees' fear that their level of activity will be reported to managers and many other practical and technical difficulties. As these challenges increase exponentially with the number of employers, subjects and sites, this study was limited to a small number of subjects all working for the same employer on the same jobsite. Still, challenges are often unpredictable and lessons learned from this study are expected to guide both our and other researchers' continuation of this work. Originality/value - The time effect on the physiological cost of work has not been considered in previous studies. Thus, this study is noteworthy owing to the depth of the data collected rather than the breadth of the data.
Keywords
Concrete; Construction Industry; Costing; Human Resource Management; Occupational Health; Personnel; Physiology; Physiological Cost; Concrete Construction Activity; Construction Workers; Summer; Autumn; Construction Trade; Working Heart Rate; Relative Heart Rate; Resting Heart Rate; Employee Fear; Jobsite; Heart-rate Strain; Stress; Work; Risk; Management; Fusion; Model; Index; Biosensing And Environmental Sensing; Occupational Safety And Health; Threshold Limit Value; Work Physiology
Pan, Haixiao; Li, Jing; Shen, Qing; Shi, Cheng. (2017). What Determines Rail Transit Passenger Volume? Implications for Transit Oriented Development Planning. Transportation Research: Part D, 57, 52 – 63.
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Abstract
Transit oriented development (TOD) has been an important topic for urban transportation planning research and practice. This paper is aimed at empirically examining the effect of rail transit station-based TOD on daily station passenger volume. Using integrated circuit (IC) card data on metro passenger volumes and cellular signaling data on the spatial distribution of human activities in Shanghai, the research identifies variations in ridership among rail transit stations. Then, regression analysis is performed using passenger volume in each station as the dependent variable. Explanatory variables include station area employment and population, residents' commuting distances, metro network accessibility, status as interchange station, and coupling with commercial activity centers. The main findings are: (1) Passenger volume is positively associated with employment density and residents' commuting distance around station; (2) stations with earlier opening dates and serving as transfer nodes tend to have positive association with passenger volumes; (3) metro stations better integrated with nearby commercial development tend to have larger passenger volumes. Several implications are drawn for TOD planning: (1) TOD planning should be integrated with rail transit network planning; (2) location of metro stations should be coupled with commercial development; (3) high employment densities should be especially encouraged as a key TOD feature; and (4) interchange stations should be more strategically positioned in the planning for rail transit network.
Keywords
Railroad Passenger Traffic; Transportation; Public Transit; Volume Measurements; Smart Cards; Mathematical Models; Accessibility; Density; Rail Transit Passenger Volume; Spatial Coupling Effect; Tod; Land-use; Built Environment; Travel-demand; Mode Choice; Impacts; Distance
Kang, Mingyu; Moudon, Anne Vernez; Kim, Haena; Boyle, Linda Ng. (2019). Intersections and Non-Intersections: A Protocol for Identifying Pedestrian Crash Risk Locations in GIS. International Journal Of Environmental Research And Public Health, 16(19).
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Abstract
Intersection and non-intersection locations are commonly used as spatial units of analysis for modeling pedestrian crashes. While both location types have been previously studied, comparing results is difficult given the different data and methods used to identify crash-risk locations. In this study, a systematic and replicable protocol was developed in GIS (Geographic Information System) to create a consistent spatial unit of analysis for use in pedestrian crash modelling. Four publicly accessible datasets were used to identify unique intersection and non-intersection locations: Roadway intersection points, roadway lanes, legal speed limits, and pedestrian crash records. Two algorithms were developed and tested using five search radii (ranging from 20 to 100 m) to assess the protocol reliability. The algorithms, which were designed to identify crash-risk locations at intersection and non-intersection areas detected 87.2% of the pedestrian crash locations (r: 20 m). Agreement rates between algorithm results and the crash data were 94.1% for intersection and 98.0% for non-intersection locations, respectively. The buffer size of 20 m generally showed the highest performance in the analyses. The present protocol offered an efficient and reliable method to create spatial analysis units for pedestrian crash modeling. It provided researchers a cost-effective method to identify unique intersection and non-intersection locations. Additional search radii should be tested in future studies to refine the capture of crash-risk locations.
Keywords
Traffic Crash; Walking; Collisions; Accidents; Models; Pedestrian Safety; Spatial Autocorrelation; Algorithm
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
Nemati, Kamran M.; Uhlmeyer, Jeff S. (2021). Accelerated Construction of Urban Intersections with Portland Cement Concrete Pavement (PCCP). Case Studies In Construction Materials, 14.
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Abstract
The frequent maintenance required on asphalt concrete (AC) pavement sections has made reconstruction with portland cement concrete pavement (PCCP) a feasible alternative. However, many constructability issues need to be addressed in order to realize the full potential of this alternative. Accelerated paving encompasses three classes of activities: methods to accelerate the rate of strength gain, methods to minimize the construction time, and traffic control strategies to minimize user delay. In this paper a case study will be presented in which an AC intersection was reconstructed with portland cement concrete pavement. The entire reconstruction of the intersection, including demolition of the AC pavement and its replacement with PCCP, took place over a period of three days, starting on Thursday evening and opening the intersection to the traffic on Sunday afternoon. This paper documents this effort in order to provide practitioners additional options for rapid reconstruction of urban intersections and includes documentation of the construction process, traffic management strategies, and an analysis of the costs. The results of this investigation can be used to educate pavement construction professionals and the academic community on the use of PCCP for accelerated reconstruction of major urban intersections with minimal user and traffic disruption, using innovative construction techniques and traffic management optimization principles. This investigation produced valuable information to demonstrate that concrete pavements can be constructed efficiently and quickly. (C) 2021 The Authors. Published by Elsevier Ltd.
Keywords
Concrete; Accelerated Construction; Pavement; Portland Cement Concrete Pavement; Maturity Method
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